Fundamental physical constants -- CODATA  2022
   (2022 complete listing from http://physics.nist.gov.constants below1)
   (2018 complete listing from http://physics.nist.gov.constants below2)
   (also see NONSI_IN.HTM)

note: entries in POWER OF TEN column are magnitudes with negative signs part of the numerical value while
 negative signs in the Value column indicate polarity and are ignored calculating POWER OF TEN magnitudes

  Quantity               rounded to 7 places: POWER OF TEN        Value                 Uncertainty           Unit
-----------------------------------------------------------------------------------------------------------------------------
electron mag. mom. to Bohr magneton ratio        0.0005033  -1.001 159 652 180 46    0.000 000 000 000 18     

proton-neutron mass ratio                      - 0.0005982  0.998 623 477 97         0.000 000 000 40         
neutron-proton mass ratio                        0.0005982  1.001 378 419 46         0.000 000 000 40         

proton relative atomic mass                      0.0031487  1.007 276 466 5789       0.000 000 000 0083       
proton mass in u                                 0.0031487  1.007 276 466 5789       0.000 000 000 0083       u
neutron relative atomic mass                     0.0037469  1.008 664 916 06         0.000 000 000 40         
neutron mass in u                                0.0037469  1.008 664 916 06         0.000 000 000 40         u
triton to proton mag. mom. ratio                 0.0280178  1.066 639 9189           0.000 000 0021           
W to Z mass ratio                              - 0.0548023  0.881 45                 0.000 13                 
Sackur-Tetrode constant (1 K, 100 kPa)           0.0613422  -1.151 707 534 96        0.000 000 000 47         
Sackur-Tetrode constant (1 K, 101.325 kPa)       0.0662777  -1.164 870 521 49        0.000 000 000 47         
deuteron g factor                              - 0.0667972  0.857 438 2335           0.000 000 0022           
deuteron mag. mom. to nuclear magneton ratio   - 0.0667972  0.857 438 2335           0.000 000 0022           
neutron-proton mass diff.   "   equiv. in MeV    0.1117102  1.293 332 51             0.000 000 38             MeV
shld. helion to shield. proton mag. mom. rat.  - 0.1181669  -0.761 786 1334          0.000 000 0031           
shielded  "  to proton mag. mom. ratio         - 0.1181781  -0.761 766 577 21        0.000 000 000 66         
neutron to shielded proton mag. mom. ratio     - 0.1643114  -0.684 996 94            0.000 000 16             

neutron-proton mag. mom. ratio                 - 0.1643225  -0.684 979 35            0.000 000 16             
proton-neutron mag. mom. ratio                   0.1643225  -1.459 898 02            0.000 000 34             

Bohr magneton in K/T                           - 0.1728157  0.671 713 814 72         0.000 000 000 21         K T^-1

neutron-tau mass ratio                         - 0.2767258  0.528 779                0.000 036                
tau-neutron mass ratio                           0.2767260  1.891 15                 0.000 13                 

proton-tau mass ratio                          - 0.2773241  0.528 051                0.000 036                
tau-proton mass ratio                            0.2773249  1.893 76                 0.000 13                 

tau mass in u                                    0.2804737  1.907 54                 0.000 13                 u
neutron mag. mom. to nuclear magneton ratio      0.2817247  -1.913 042 76            0.000 000 45             
natural unit of energy in MeV                  - 0.2915800  0.510 998 950 69         0.000 000 000 16         MeV
electron mass energy equivalent in MeV         - 0.2915800  0.510 998 950 69         0.000 000 000 16         MeV
natural unit of momentum in MeV/c              - 0.2915800  0.510 998 950 69         0.000 000 000 16         MeV/c
deuteron-proton mass ratio                       0.3008144  1.999 007 501 2699       0.000 000 000 0084       
electron g factor                                0.3015333  -2.002 319 304 360 92    0.000 000 000 000 36     
muon g factor                                    0.3015361  -2.002 331 841 23        0.000 000 000 82         
deuteron relative atomic mass                    0.3039631  2.013 553 212 544        0.000 000 000 015        
deuteron mass in u                               0.3039631  2.013 553 212 544        0.000 000 000 015        u
shld.  " mag. mom. to nuclear magneton ratio     0.3278691  -2.127 497 7624          0.000 000 0017           
helion mag. mom. to nuclear magneton ratio       0.3278952  -2.127 625 3498          0.000 000 0017           
deuteron-neutron mag. mom. ratio               - 0.3485218  -0.448 206 52            0.000 000 11             
shld.     "   "  "  to nuclear magneton ratio    0.4460360  2.792 775 648            0.000 000 011            
proton mag. mom. to nuclear magneton ratio       0.4460472  2.792 847 344 63         0.000 000 000 82         
triton mag. mom. to nuclear magneton ratio       0.4740650  2.978 962 4650           0.000 000 0059           
helion-proton mass ratio                         0.4761289  2.993 152 671 552        0.000 000 000 070        
triton-proton mass ratio                         0.4762107  2.993 717 034 03         0.000 000 000 10         
helion relative atomic mass                      0.4792776  3.014 932 246 932        0.000 000 000 074        
helion mass in u                                 0.4792776  3.014 932 246 932        0.000 000 000 074        u
triton relative atomic mass                      0.4793594  3.015 500 715 97         0.000 000 000 10         
triton mass in u                                 0.4793594  3.015 500 715 97         0.000 000 000 10         u
muon-proton mag. mom. ratio                      0.5028837  -3.183 345 146           0.000 000 071            
deuteron-proton mag. mom. ratio                - 0.5128444  0.307 012 209 30         0.000 000 000 79         
neutron g factor                                 0.5827547  -3.826 085 52            0.000 000 90             
alpha particle-proton mass ratio                 0.5990748  3.972 599 690 252        0.000 000 000 070        
alpha particle relative atomic mass              0.6022235  4.001 506 179 129        0.000 000 000 062        
alpha particle mass in u                         0.6022235  4.001 506 179 129        0.000 000 000 062        u
helion g factor                                  0.6289252  -4.255 250 6995          0.000 000 0034           
weak mixing angle                              - 0.6515978  0.223 05                 0.000 23                 
proton g factor                                  0.7470772  5.585 694 6893           0.000 000 0016           
triton g factor                                  0.7750950  5.957 924 930            0.000 000 012            
nuclear magneton in MHz/T                        0.8821027  7.622 593 2188           0.000 000 0024           MHz T^-1
molar gas constant                               0.9198342  8.314 462 618...         (exact)                  J mol^-1 K^-1
muon mass in u                                 - 0.9452762  0.113 428 9257           0.000 000 0025           u

muon-proton mass ratio                         - 0.9484249  0.112 609 5262           0.000 000 0025           
proton-muon mass ratio                           0.9484249  8.880 243 38             0.000 000 20             

muon mag. mom. to nuclear magneton ratio         0.9489309  -8.890 597 04            0.000 000 20             

muon-neutron mass ratio                        - 0.9490231  0.112 454 5168           0.000 000 0025           
neutron-muon mass ratio                          0.9490231  8.892 484 08             0.000 000 20             

standard acceleration of gravity                 0.9915207  9.806 65                 (exact)                  m s^-2
Rydberg constant times hc in eV                  1.1337207  13.605 693 122 990       0.000 000 000 015        eV

tau-muon mass ratio                              1.2257485  16.8170                  0.0011                   
muon-tau mass ratio                            - 1.2257495  5.946 35 e-2             0.000 40 e-2             

electron volt-hartree relationship             - 1.4347506  3.674 932 217 5665 e-2   0.000 000 000 0040 e-2   E_h
Hartree energy in eV                             1.4347507  27.211 386 245 981       0.000 000 000 030        eV
hartree-electron volt relationship               1.4347507  27.211 386 245 981       0.000 000 000 030        eV
atomic unit of electric potential                1.4347507  27.211 386 245 981       0.000 000 000 030        V
neutron gyromag. ratio in MHz/T                  1.4648574  29.164 6935              0.000 0069               MHz T^-1
shielded helion gyromag. ratio in MHz/T          1.5110019  32.434 100 033           0.000 000 028            MHz T^-1
nuclear magneton in inverse meter per tesla    - 1.5947180  2.542 623 410 09 e-2     0.000 000 000 79 e-2     m^-1 T^-1
shielded proton gyromag. ratio in MHz/T          1.6291688  42.576 385 43            0.000 000 17             MHz T^-1
proton gyromag. ratio in MHz/T                   1.6291799  42.577 478 461           0.000 000 018            MHz T^-1
molar vol. of ideal gas (273.15 K, 100 kPa)    - 1.6437646  22.710 954 64... e-3     (exact)                  m^3 mol^-1
molar vol. of  "  gas (273.15 K, 101.325 kPa)  - 1.6494812  22.413 969 54... e-3     (exact)                  m^3 mol^-1
Bohr magneton in inverse meter per tesla         1.6691908  46.686 447 719           0.000 000 015            m^-1 T^-1
Boltzmann   "   in inverse meter per kelvin      1.8420065  69.503 480 04...         (exact)                  m^-1 K^-1
inverse meter-kelvin relationship              - 1.8420066  1.438 776 877... e-2     (exact)                  K
second radiation constant                      - 1.8420066  1.438 776 877... e-2     (exact)                  m K
kelvin-inverse meter relationship                1.8420066  69.503 480 04...         (exact)                  m^-1
molar mass of carbon-12                        - 1.9208188  12.000 000 0126 e-3      0.000 000 0037 e-3       kg mol^-1
muon mass energy equivalent in MeV               2.0239039  105.658 3755             0.000 0023               MeV

inverse fine-structure constant                  2.1368347  137.035 999 177          0.000 000 021            
fine-structure constant                        - 2.1368347  7.297 352 5643 e-3       0.000 000 0011 e-3       

atomic unit of current                         - 2.1789047  6.623 618 237 5082 e-3   0.000 000 000 0072 e-3   A
reduced Planck constant times c in MeV fm        2.2951865  197.326 980 4...         (exact)                  MeV fm
muon mag. mom. to Bohr magneton ratio          - 2.3149779  -4.841 970 48 e-3        0.000 000 11 e-3         
electron-muon mag. mom. ratio                    2.3154812  206.766 9881             0.000 0046               

muon-electron mass ratio                         2.3154839  206.768 2827             0.000 0046               
electron-muon mass ratio                       - 2.3154839  4.836 331 70 e-3         0.000 000 11 e-3         

alpha particle molar mass                      - 2.3977765  4.001 506 1833 e-3       0.000 000 0012 e-3       kg mol^-1
triton molar mass                              - 2.5206406  3.015 500 719 13 e-3     0.000 000 000 94 e-3     kg mol^-1
helion molar mass                              - 2.5207224  3.014 932 250 10 e-3     0.000 000 000 94 e-3     kg mol^-1
Wien wavelength displacement law constant      - 2.5379358  2.897 771 955... e-3     (exact)                  m K
characteristic impedance of vacuum               2.5760306  376.730 313 412          0.000 000 059            ohm
deuteron molar mass                            - 2.6960369  2.013 553 214 66 e-3     0.000 000 000 63 e-3     kg mol^-1
tau molar mass                                 - 2.7195263  1.907 54 e-3             0.000 13 e-3             kg mol^-1
triton mag. mom. to Bohr magneton ratio        - 2.7898438  1.622 393 6648 e-3       0.000 000 0032 e-3       
proton mag. mom. to Bohr magneton ratio        - 2.8178616  1.521 032 202 30 e-3     0.000 000 000 45 e-3     
shld.     "   "  "  to Bohr magneton ratio     - 2.8178727  1.520 993 1551 e-3       0.000 000 0062 e-3       
electron-proton mag. mom. ratio                  2.8183649  -658.210 687 89          0.000 000 19             
electron to shielded proton mag. mom. ratio      2.8183761  -658.227 5856            0.000 0027               
luminous efficacy                                2.8344207  683                      (exact)                  lm W^-1
neutron-proton mass difference in u            - 2.8574699  1.388 449 48 e-3         0.000 000 40 e-3         u
muon mag. mom. anomaly                         - 2.9333310  1.165 920 62 e-3         0.000 000 41 e-3         
electron mag. mom. anomaly                     - 2.9356723  1.159 652 180 46 e-3     0.000 000 000 18 e-3     
helion mag. mom. to Bohr magneton ratio        - 2.9360136  -1.158 740 980 83 e-3    0.000 000 000 94 e-3     
shld.  " mag. mom. to Bohr magneton ratio      - 2.9360397  -1.158 671 494 57 e-3    0.000 000 000 94 e-3     
electron to shielded helion mag. mom. ratio      2.9365430  864.058 239 86           0.000 000 70             
atomic mass constant energy equivalent in MeV    2.9691801  931.494 103 72           0.000 000 29             MeV
proton mass energy equivalent in MeV             2.9723288  938.272 089 43           0.000 000 29             MeV
neutron mass energy equivalent in MeV            2.9729270  939.565 421 94           0.000 000 48             MeV
neutron mag. mom. to Bohr magneton ratio       - 2.9821841  -1.041 875 65 e-3        0.000 000 25 e-3         

neutron-electron mag. mom. ratio               - 2.9826874  1.040 668 84 e-3         0.000 000 24 e-3         
electron-neutron mag. mom. ratio                 2.9826874  960.920 48               0.000 23                 

neutron molar mass                             - 2.9962531  1.008 664 917 12 e-3     0.000 000 000 51 e-3     kg mol^-1
proton molar mass                              - 2.9968513  1.007 276 467 64 e-3     0.000 000 000 31 e-3     kg mol^-1
quantum of circulation times 2                 - 3.1382330  7.273 895 0934 e-4       0.000 000 0023 e-4       m^2 s^-1
tau energy equivalent                            3.2496532  1776.86                  0.12                     MeV
electron relative atomic mass                  - 3.2607601  5.485 799 090 441 e-4    0.000 000 000 097 e-4    
electron mass in u                             - 3.2607601  5.485 799 090 441 e-4    0.000 000 000 097 e-4    u

proton-electron mass ratio                       3.2639088  1836.152 673 426         0.000 000 032            
electron-proton mass ratio                     - 3.2639088  5.446 170 214 889 e-4    0.000 000 000 094 e-4    

electron mag. mom. to nuclear magneton ratio   - 3.2644121  -1838.281 971 877        0.000 000 032            

neutron-electron mass ratio                      3.2645070  1838.683 662 00          0.000 000 74             
electron-neutron mass ratio                    - 3.2645070  5.438 673 4416 e-4       0.000 000 0022 e-4       

deuteron mass energy equivalent in MeV           3.2731432  1875.612 945 00          0.000 000 58             MeV
deuteron mag. mom. to Bohr magneton ratio      - 3.3307059  4.669 754 568 e-4        0.000 000 012 e-4        

electron-deuteron mag. mom. ratio                3.3312093  -2143.923 4921           0.000 0056               
deuteron-electron mag. mom. ratio              - 3.3312093  -4.664 345 550 e-4       0.000 000 012 e-4        

nuclear magneton in K/T                        - 3.4367245  3.658 267 7706 e-4       0.000 000 0011 e-4       K T^-1
quantum of circulation                         - 3.4392630  3.636 947 5467 e-4       0.000 000 0011 e-4       m^2 s^-1
helion mass energy equivalent in MeV             3.4484577  2808.391 611 12          0.000 000 88             MeV
triton mass energy equivalent in MeV             3.4485395  2808.921 136 68          0.000 000 88             MeV

tau-electron mass ratio                          3.5412334  3477.23                  0.23                     
electron-tau mass ratio                        - 3.5412338  2.875 85 e-4             0.000 19 e-4             

electron-deuteron mass ratio                   - 3.5647232  2.724 437 107 629 e-4    0.000 000 000 047 e-4    
deuteron-electron mass ratio                     3.5647232  3670.482 967 655         0.000 000 063            

alpha particle mass energy equivalent in MeV     3.5714036  3727.379 4118            0.000 0012               MeV

electron-helion mass ratio                     - 3.7400377  1.819 543 074 649 e-4    0.000 000 000 053 e-4    
helion-electron mass ratio                       3.7400377  5495.885 279 84          0.000 000 16             

electron-triton mass ratio                     - 3.7401195  1.819 200 062 327 e-4    0.000 000 000 068 e-4    
triton-electron mass ratio                       3.7401195  5496.921 535 51          0.000 000 21             

electron to alpha particle mass ratio          - 3.8629836  1.370 933 554 733 e-4    0.000 000 000 032 e-4    
alpha particle-electron mass ratio               3.8629836  7294.299 541 71          0.000 000 17             

muon molar mass                                - 3.9452762  1.134 289 258 e-4        0.000 000 025 e-4        kg mol^-1
electron volt-kelvin relationship                4.0646271  1.160 451 812... e4      (exact)                  K
kelvin-electron volt relationship              - 4.0646271  8.617 333 262... e-5     (exact)                  eV
Boltzmann constant in eV/K                     - 4.0646271  8.617 333 262... e-5     (exact)                  eV K^-1
conductance quantum                            - 4.1108052  7.748 091 729... e-5     (exact)                  S
inverse of conductance quantum                   4.1108052  12 906.403 72...         (exact)                  ohm
helion shielding shift                         - 4.2220875  5.996 7029 e-5           0.000 0023 e-5           
Bohr magneton in eV/T                          - 4.2374428  5.788 381 7982 e-5       0.000 000 0018 e-5       eV T^-1
conventional value of von Klitzing constant      4.4118352  25 812.807               (exact)                  ohm
von Klitzing constant                            4.4118352  25 812.807 45...         (exact)                  ohm
electron gyromag. ratio in MHz/T                 4.4475449  28 024.951 3861          0.000 0087               MHz T^-1
proton mag. shielding correction               - 4.5905488  2.567 15 e-5             0.000 41 e-5             
molar volume of silicon                        - 4.9186948  1.205 883 199 e-5        0.000 000 060 e-5        m^3 mol^-1
Fermi coupling constant                        - 4.9331604  1.166 3787 e-5           0.000 0006 e-5           GeV^-2
Faraday constant                                 4.9844613  96 485.332 12...         (exact)                  C mol^-1
standard-state pressure                          5.0000000  100 000                  (exact)                  Pa
standard atmosphere                              5.0057166  101 325                  (exact)                  Pa
atomic unit of mag. flux density                 5.3711635  2.350 517 570 77 e5      0.000 000 000 73 e5      T

hartree-kelvin relationship                      5.4993778  3.157 750 248 0398 e5    0.000 000 000 0034 e5    K
kelvin-hartree relationship                    - 5.4993778  3.166 811 563 4564 e-6   0.000 000 000 0035 e-6   E_h

vacuum mag. permeability                       - 5.9007901  1.256 637 061 27 e-6     0.000 000 000 20 e-6     N A^-2
inverse meter-electron volt relationship       - 5.9066337  1.239 841 984... e-6     (exact)                  eV
electron volt-inverse meter relationship         5.9066337  8.065 543 937... e5      (exact)                  m^-1
electron molar mass                            - 6.2607601  5.485 799 0962 e-7       0.000 000 0017 e-7       kg mol^-1
atomic unit of velocity                          6.3399860  2.187 691 262 16 e6      0.000 000 000 34 e6      m s^-1
Rydberg constant                                 7.0403543  10 973 731.568 157       0.000 012                m^-1
atomic unit of force                           - 7.0841401  8.238 723 5038 e-8       0.000 000 0013 e-8       N
Stefan-Boltzmann constant                      - 7.2463883  5.670 374 419... e-8     (exact)                  W m^-2 K^-4

hartree-inverse meter relationship               7.3413843  2.194 746 313 6314 e7    0.000 000 000 0024 e7    m^-1
inverse meter-hartree relationship             - 7.3413843  4.556 335 252 9132 e-8   0.000 000 000 0050 e-8   E_h

nuclear magneton in eV/T                       - 7.5013516  3.152 451 254 17 e-8     0.000 000 000 98 e-8     eV T^-1

hartree-atomic mass unit relationship          - 7.5344294  2.921 262 317 97 e-8     0.000 000 000 91 e-8     u
atomic mass unit-hartree relationship            7.5344294  3.423 177 6922 e7        0.000 000 0011 e7        E_h

shielding difference of t and p in HT          - 7.6207852  2.394 50 e-8             0.000 20 e-8             
Planck mass                                    - 7.6622545  2.176 434 e-8            0.000 024 e-8            kg
shielding difference of d and p in HD          - 7.7016492  1.987 70 e-8             0.000 10 e-8             
proton charge to mass quotient                   7.9813126  9.578 833 1430 e7        0.000 000 0030 e7        C kg^-1
neutron gyromag. ratio                           8.2630373  1.832 471 74 e8          0.000 000 43 e8          s^-1 T^-1
shielded helion gyromag. ratio                   8.3091817  2.037 894 6078 e8        0.000 000 0018 e8        s^-1 T^-1
shielded proton gyromag. ratio                   8.4273487  2.675 153 194 e8         0.000 000 011 e8         s^-1 T^-1
proton gyromag. ratio                            8.4273598  2.675 221 8708 e8        0.000 000 0011 e8        s^-1 T^-1
inverse meter-hertz relationship                 8.4768207  299 792 458              (exact)                  Hz
speed of light in vacuum                         8.4768207  299 792 458              (exact)                  m s^-1
natural unit of velocity                         8.4768207  299 792 458              (exact)                  m s^-1
hertz-inverse meter relationship               - 8.4768207  3.335 640 951... e-9     (exact)                  m^-1

electron volt-atomic mass unit relationship    - 8.9691801  1.073 544 100 83 e-9     0.000 000 000 33 e-9     u
atomic mass unit-electron volt relationship      8.9691801  9.314 941 0372 e8        0.000 000 0029 e8        eV

lattice parameter of silicon                   - 9.2651186  5.431 020 511 e-10       0.000 000 089 e-10       m
triton mass energy equivalent                  - 9.3467501  4.500 387 8119 e-10      0.000 000 0014 e-10      J
helion mass energy equivalent                  - 9.3468319  4.499 539 4185 e-10      0.000 000 0014 e-10      J
molar Planck constant                          - 9.3989931  3.990 312 712... e-10    (exact)                  J Hz^-1 mol^-1
deuteron mass energy equivalent                - 9.5221464  3.005 063 234 91 e-10    0.000 000 000 94 e-10    J
tau mass energy equivalent                     - 9.5456369  2.846 84 e-10            0.000 19 e-10            J
lattice spacing of ideal Si (220)              - 9.7166636  1.920 155 716 e-10       0.000 000 032 e-10       m
neutron mass energy equivalent                 - 9.8223626  1.505 349 765 14 e-10    0.000 000 000 76 e-10    J
proton mass energy equivalent                  - 9.8229608  1.503 277 618 02 e-10    0.000 000 000 47 e-10    J

atomic mass constant energy equivalent         - 9.8261095  1.492 418 087 68 e-10    0.000 000 000 46 e-10    J
atomic mass unit-joule relationship            - 9.8261095  1.492 418 087 68 e-10    0.000 000 000 46 e-10    J
joule-atomic mass unit relationship              9.8261095  6.700 535 2471 e9        0.000 000 0021 e9        u

atomic unit of permittivity                    - 9.9536414  1.112 650 056 20 e-10    0.000 000 000 17 e-10    F m^-1
hyperfine transition frequency of Cs-133         9.9634399  9 192 631 770            (exact)                  Hz
Angstrom star                                  - 9.9999935  1.000 014 95 e-10        0.000 000 90 e-10        m
alpha particle mass energy equivalent          -09.2238860  5.971 920 1997 e-10      0.000 000 0019 e-10      J
Bohr magneton in Hz/T                           10.1460115  1.399 624 491 71 e10     0.000 000 000 44 e10     Hz T^-1
Newtonian constant of gravitation              -10.1755943  6.674 30 e-11            0.000 15 e-11            m^3 kg^-1 s^-2
Bohr radius                                    -10.2763989  5.291 772 105 44 e-11    0.000 000 000 82 e-11    m
atomic unit of length                          -10.2763989  5.291 772 105 44 e-11    0.000 000 000 82 e-11    m
kelvin-hertz relationship                       10.3188273  2.083 661 912... e10     (exact)                  Hz
Boltzmann constant in Hz/K                      10.3188273  2.083 661 912... e10     (exact)                  Hz K^-1
hertz-kelvin relationship                      -10.3188273  4.799 243 073... e-11    (exact)                  K
Wien frequency displacement law constant        10.7692980  5.878 925 757... e10     (exact)                  Hz K^-1
muon mass energy equivalent                    -10.7713857  1.692 833 804 e-11       0.000 000 038 e-11       J
vacuum electric permittivity                   -11.0528513  8.854 187 8188 e-12      0.000 000 0014 e-12      F m^-1
electron charge to mass quotient                11.2452214  -1.758 820 008 38 e11    0.000 000 000 55 e11     C kg^-1
electron gyromag. ratio                         11.2457247  1.760 859 627 84 e11     0.000 000 000 55 e11     s^-1 T^-1
Compton wavelength                             -11.6150537  2.426 310 235 38 e-12    0.000 000 000 76 e-12    m
atomic unit of electric field                   11.7111495  5.142 206 751 12 e11     0.000 000 000 80 e11     V m^-1
atomic unit of charge density                   12.0339070  1.081 202 386 77 e12     0.000 000 000 51 e12     C m^-3
reduced Compton wavelength                     -12.4132335  3.861 592 6744 e-13      0.000 000 0012 e-13      m
natural unit of length                         -12.4132335  3.861 592 6744 e-13      0.000 000 0012 e-13      m
neutron-proton mass diff. energy equivalent    -12.6835794  2.072 147 12 e-13        0.000 000 60 e-13        J
Molybdenum x unit                              -12.9990891  1.002 099 52 e-13        0.000 000 53 e-13        m
Copper x unit                                  -12.9990989  1.002 076 97 e-13        0.000 000 28 e-13        m

atomic mass unit-kelvin relationship            13.0338072  1.080 954 020 67 e13     0.000 000 000 34 e13     K
kelvin-atomic mass unit relationship           -13.0338072  9.251 087 2884 e-14      0.000 000 0029 e-14      u

natural unit of energy                         -13.0868696  8.187 105 7880 e-14      0.000 000 0026 e-14      J
electron mass energy equivalent                -13.0868696  8.187 105 7880 e-14      0.000 000 0026 e-14      J
muon Compton wavelength                        -13.9305376  1.173 444 110 e-14       0.000 000 026 e-14       m
electron volt-hertz relationship                14.3834544  2.417 989 242... e14     (exact)                  Hz
hertz-electron volt relationship               -14.3834544  4.135 667 696... e-15    (exact)                  eV
Planck constant in eV/Hz                       -14.3834544  4.135 667 696... e-15    (exact)                  eV Hz^-1
classical electron radius                      -14.5500682  2.817 940 3205 e-15      0.000 000 0013 e-15      m
deuteron rms charge radius                     -14.6720733  2.127 78 e-15            0.000 27 e-15            m
mag. flux quantum                              -14.6844844  2.067 833 848... e-15    (exact)                  Wb
Josephson constant                              14.6844844  483 597.848 4... e9      (exact)                  Hz V^-1
conventional value of Josephson constant       -14.6844844  483 597.9 e9             (exact)                  Hz V^-1
reduced muon Compton wavelength                -14.7287175  1.867 594 306 e-15       0.000 000 042 e-15       m
alpha particle rms charge radius               -14.7750787  1.6785 e-15              0.0021 e-15              m

inverse meter-atomic mass unit relationship    -14.8758138  1.331 025 048 24 e-15    0.000 000 000 41 e-15    u
atomic mass unit-inverse meter relationship     14.8758138  7.513 006 6209 e14       0.000 000 0023 e14       m^-1

proton Compton wavelength                      -14.8789625  1.321 409 853 60 e-15    0.000 000 000 41 e-15    m
neutron Compton wavelength                     -14.8795607  1.319 590 903 82 e-15    0.000 000 000 67 e-15    m
proton rms charge radius                       -15.0753331  8.4075 e-16              0.0064 e-16              m
tau Compton wavelength                         -15.1562871  6.977 71 e-16            0.000 47 e-16            m
elementary charge over h-bar                    15.1816342  1.519 267 447... e15     (exact)                  A J^-1
reduced Planck constant in eV s                -15.1816342  6.582 119 569... e-16    (exact)                  eV s
natural unit of action in eV s                 -15.1816342  6.582 119 569... e-16    (exact)                  eV s
first radiation constant                       -15.4269227  3.741 771 852... e-16    (exact)                  W m^2
Rydberg constant times c in Hz                  15.5171750  3.289 841 960 2500 e15   0.000 000 000 0036 e15   Hz
reduced proton Compton wavelength              -15.6771423  2.103 089 100 51 e-16    0.000 000 000 66 e-16    m
reduced neutron Compton wavelength             -15.6777406  2.100 194 1520 e-16      0.000 000 0011 e-16      m

hertz-hartree relationship                     -15.8182050  1.519 829 846 0574 e-16  0.000 000 000 0017 e-16  E_h
hartree-hertz relationship                      15.8182050  6.579 683 920 4999 e15   0.000 000 000 0072 e15   Hz

first radiation   "     for spectral radiance  -15.9240726  1.191 042 972... e-16    (exact)                  W m^2 sr^-1
reduced tau Compton wavelength                 -15.9544666  1.110 538 e-16           0.000 075 e-16           m
atomic unit of time                            -16.6163849  2.418 884 326 5864 e-17  0.000 000 000 0026 e-17  s
joule-kilogram relationship                    -16.9536414  1.112 650 056... e-17    (exact)                  kg
kilogram-joule relationship                     16.9536414  8.987 551 787... e16     (exact)                  J

joule-hartree relationship                      17.3605389  2.293 712 278 3969 e17   0.000 000 000 0025 e17   E_h
Hartree energy                                 -17.3605389  4.359 744 722 2060 e-18  0.000 000 000 0048 e-18  J
atomic unit of energy                          -17.3605389  4.359 744 722 2060 e-18  0.000 000 000 0048 e-18  J
hartree-joule relationship                     -17.3605389  4.359 744 722 2060 e-18  0.000 000 000 0048 e-18  J

Rydberg constant times hc in J                 -17.6615689  2.179 872 361 1030 e-18  0.000 000 000 0024 e-18  J
atomic unit of charge                          -18.7952896  1.602 176 634 e-19       (exact)                  C
elementary charge                              -18.7952896  1.602 176 634 e-19       (exact)                  C
electron volt                                  -18.7952896  1.602 176 634 e-19       (exact)                  J
electron volt-joule relationship               -18.7952896  1.602 176 634 e-19       (exact)                  J
joule-electron volt relationship                18.7952896  6.241 509 074... e18     (exact)                  eV
Planck mass energy equivalent in GeV            19.0866765  1.220 890 e19            0.000 014 e19            GeV
natural unit of time                           -20.8900542  1.288 088 666 44 e-21    0.000 000 000 40 e-21    s
natural unit of momentum                       -21.5636903  2.730 924 534 46 e-22    0.000 000 000 85 e-22    kg m s^-1
atomic unit of electric field gradient          21.9875484  9.717 362 4424 e21       0.000 000 0030 e21       V m^-2
atomic unit of mag. dipole mom.                -22.7317024  1.854 802 013 15 e-23    0.000 000 000 58 e-23    J T^-1
kelvin-joule relationship                      -22.8599167  1.380 649 e-23           (exact)                  J
Boltzmann constant                             -22.8599167  1.380 649 e-23           (exact)                  J K^-1
joule-kelvin relationship                       22.8599167  7.242 970 516... e22     (exact)                  K
electron mag. mom.                             -23.0322291  -9.284 764 6917 e-24     0.000 000 0029 e-24      J T^-1
Bohr magneton                                  -23.0327324  9.274 010 0657 e-24      0.000 000 0029 e-24      J T^-1

atomic mass unit-hertz relationship             23.3526345  2.252 342 721 85 e23     0.000 000 000 70 e23     Hz
hertz-atomic mass unit relationship            -23.3526345  4.439 821 6590 e-24      0.000 000 0014 e-24      u

atomic unit of momentum                        -23.7005250  1.992 851 915 45 e-24    0.000 000 000 31 e-24    kg m s^-1
Avogadro constant                               23.7797509  6.022 140 76 e23         (exact)                  mol^-1
inverse meter-joule relationship               -24.7019233  1.986 445 857... e-25    (exact)                  J
joule-inverse meter relationship                24.7019233  5.034 116 567... e24     (exact)                  m^-1
muon mag. mom.                                 -25.3477103  -4.490 448 30 e-26       0.000 000 10 e-26        J T^-1
Loschmidt constant (273.15 K, 100 kPa)          25.4235155  2.651 645 804... e25     (exact)                  m^-3
Loschmidt constant (273.15 K, 101.325 kPa)      25.4292321  2.686 780 111... e25     (exact)                  m^-3
triton mag. mom.                               -25.8225762  1.504 609 5178 e-26      0.000 000 0030 e-26      J T^-1
proton mag. mom.                               -25.8505940  1.410 606 795 45 e-26    0.000 000 000 60 e-26    J T^-1
shielded proton mag. mom.                      -25.8506052  1.410 570 5830 e-26      0.000 000 0058 e-26      J T^-1
helion mag. mom.                               -25.9687461  -1.074 617 551 98 e-26   0.000 000 000 93 e-26    J T^-1
shielded helion mag. mom.                      -25.9687721  -1.074 553 110 35 e-26   0.000 000 000 93 e-26    J T^-1
neutron mag. mom.                              -26.0149165  -9.662 3653 e-27         0.000 0023 e-27          J T^-1
alpha particle mass                            -26.1775274  6.644 657 3450 e-27      0.000 000 0021 e-27      kg
nuclear magneton                               -26.2966412  5.050 783 7393 e-27      0.000 000 0016 e-27      J T^-1
triton mass                                    -26.3003915  5.007 356 7512 e-27      0.000 000 0016 e-27      kg
helion mass                                    -26.3004733  5.006 412 7862 e-27      0.000 000 0016 e-27      kg
deuteron mag. mom.                             -26.3634384  4.330 735 087 e-27       0.000 000 011 e-27       J T^-1
deuteron mass                                  -26.4757878  3.343 583 7768 e-27      0.000 000 0010 e-27      kg
tau mass                                       -26.4992779  3.167 54 e-27            0.000 21 e-27            kg
neutron mass                                   -26.7760040  1.674 927 500 56 e-27    0.000 000 000 85 e-27    kg
proton mass                                    -26.7766022  1.672 621 925 95 e-27    0.000 000 000 52 e-27    kg

atomic mass constant                           -26.7797509  1.660 539 068 92 e-27    0.000 000 000 52 e-27    kg
unified atomic mass unit                       -26.7797509  1.660 539 068 92 e-27    0.000 000 000 52 e-27    kg
atomic mass unit-kilogram relationship         -26.7797509  1.660 539 068 92 e-27    0.000 000 000 52 e-27    kg
kilogram-atomic mass unit relationship          26.7797509  6.022 140 7537 e26       0.000 000 0019 e26       u

muon mass                                      -27.7250271  1.883 531 627 e-28       0.000 000 042 e-28       kg
atomic unit of magnetizability                 -28.1028659  7.891 036 5794 e-29      0.000 000 0049 e-29      J T^-2
Thomson cross section                          -28.1770178  6.652 458 7051 e-29      0.000 000 0062 e-29      m^2
atomic unit of electric dipole mom.            -29.0716885  8.478 353 6198 e-30      0.000 000 0013 e-30      C m
neutron-proton mass difference                 -29.6372208  2.305 574 61 e-30        0.000 000 67 e-30        kg
natural unit of mass                           -30.0405110  9.109 383 7139 e-31      0.000 000 0028 e-31      kg
atomic unit of mass                            -30.0405110  9.109 383 7139 e-31      0.000 000 0028 e-31      kg
electron mass                                  -30.0405110  9.109 383 7139 e-31      0.000 000 0028 e-31      kg
Planck temperature                              32.1513036  1.416 784 e32            0.000 016 e32            K
joule-hertz relationship                        33.1787440  1.509 190 179... e33     (exact)                  Hz
hertz-joule relationship                       -33.1787440  6.626 070 15 e-34        (exact)                  J
Planck constant                                -33.1787440  6.626 070 15 e-34        (exact)                  J Hz^-1
reduced Planck constant                        -33.9769238  1.054 571 817... e-34    (exact)                  J s
atomic unit of action                          -33.9769238  1.054 571 817... e-34    (exact)                  J s
natural unit of action                         -33.9769238  1.054 571 817... e-34    (exact)                  J s

kilogram-hartree relationship                   34.3141803  2.061 485 788 7415 e34   0.000 000 000 0022 e34   E_h
hartree-kilogram relationship                  -34.3141803  4.850 870 209 5419 e-35  0.000 000 000 0053 e-35  kg

Planck length                                  -34.7914901  1.616 255 e-35           0.000 018 e-35           m
electron volt-kilogram relationship            -35.7489310  1.782 661 921... e-36    (exact)                  kg
kilogram-electron volt relationship             35.7489310  5.609 588 603... e35     (exact)                  eV
Newtonian constant of grav. over h-bar c       -38.1733532  6.708 83 e-39            0.000 15 e-39            (GeV/c^2)^-2
atomic unit of electric quadrupole mom.        -39.3480873  4.486 551 5185 e-40      0.000 000 0014 e-40      C m^2
kelvin-kilogram relationship                   -39.8135581  1.536 179 187... e-40    (exact)                  kg
kilogram-kelvin relationship                    39.8135581  6.509 657 260... e39     (exact)                  K
atomic unit of electric polarizability         -40.7828380  1.648 777 272 12 e-41    0.000 000 000 51 e-41    C^2 m^2 J^-1
inverse meter-kilogram relationship            -41.6555647  2.210 219 094... e-42    (exact)                  kg
kilogram-inverse meter relationship             41.6555647  4.524 438 335... e41     (exact)                  m^-1
Planck time                                    -43.2683108  5.391 247 e-44           0.000 060 e-44           s
kilogram-hertz relationship                     50.1323854  1.356 392 489... e50     (exact)                  Hz
hertz-kilogram relationship                    -50.1323854  7.372 497 323... e-51    (exact)                  kg
atomic unit of 1st hyperpolarizability         -52.4939875  3.206 361 2996 e-53      0.000 000 0015 e-53      C^3 m^3 J^-2
atomic unit of 2nd hyperpolarizability         -64.2051370  6.235 379 9735 e-65      0.000 000 0039 e-65      C^4 m^4 J^-3
conventional value of farad-90                              0.999 999 982 20...      (exact)                  F
molar mass constant                                         1.000 000 001 05 e-3     0.000 000 000 31 e-3     kg mol^-1
conventional value of henry-90                              1.000 000 017 79...      (exact)                  H
conventional value of ohm-90                                1.000 000 017 79...      (exact)                  ohm
conventional value of ampere-90                             1.000 000 088 87...      (exact)                  A
conventional value of coulomb-90                            1.000 000 088 87...      (exact)                  C
conventional value of volt-90                               1.000 000 106 66...      (exact)                  V
conventional value of watt-90                               1.000 000 195 53...      (exact)                  W



  Fundamental physical constants -- Complete Listing 2022 CODATA adjustment from http://physics.nist.gov.constants

  Quantity                                                       Value                 Uncertainty           Unit
-----------------------------------------------------------------------------------------------------------------------------
alpha particle-electron mass ratio                          7294.299 541 71          0.000 000 17             
alpha particle mass                                         6.644 657 3450 e-27      0.000 000 0021 e-27      kg
alpha particle mass energy equivalent                       5.971 920 1997 e-10      0.000 000 0019 e-10      J
alpha particle mass energy equivalent in MeV                3727.379 4118            0.000 0012               MeV
alpha particle mass in u                                    4.001 506 179 129        0.000 000 000 062        u
alpha particle molar mass                                   4.001 506 1833 e-3       0.000 000 0012 e-3       kg mol^-1
alpha particle-proton mass ratio                            3.972 599 690 252        0.000 000 000 070        
alpha particle relative atomic mass                         4.001 506 179 129        0.000 000 000 062        
alpha particle rms charge radius                            1.6785 e-15              0.0021 e-15              m
Angstrom star                                               1.000 014 95 e-10        0.000 000 90 e-10        m
atomic mass constant                                        1.660 539 068 92 e-27    0.000 000 000 52 e-27    kg
atomic mass constant energy equivalent                      1.492 418 087 68 e-10    0.000 000 000 46 e-10    J
atomic mass constant energy equivalent in MeV               931.494 103 72           0.000 000 29             MeV
atomic mass unit-electron volt relationship                 9.314 941 0372 e8        0.000 000 0029 e8        eV
atomic mass unit-hartree relationship                       3.423 177 6922 e7        0.000 000 0011 e7        E_h
atomic mass unit-hertz relationship                         2.252 342 721 85 e23     0.000 000 000 70 e23     Hz
atomic mass unit-inverse meter relationship                 7.513 006 6209 e14       0.000 000 0023 e14       m^-1
atomic mass unit-joule relationship                         1.492 418 087 68 e-10    0.000 000 000 46 e-10    J
atomic mass unit-kelvin relationship                        1.080 954 020 67 e13     0.000 000 000 34 e13     K
atomic mass unit-kilogram relationship                      1.660 539 068 92 e-27    0.000 000 000 52 e-27    kg
atomic unit of 1st hyperpolarizability                      3.206 361 2996 e-53      0.000 000 0015 e-53      C^3 m^3 J^-2
atomic unit of 2nd hyperpolarizability                      6.235 379 9735 e-65      0.000 000 0039 e-65      C^4 m^4 J^-3
atomic unit of action                                       1.054 571 817... e-34    (exact)                  J s
atomic unit of charge                                       1.602 176 634 e-19       (exact)                  C
atomic unit of charge density                               1.081 202 386 77 e12     0.000 000 000 51 e12     C m^-3
atomic unit of current                                      6.623 618 237 5082 e-3   0.000 000 000 0072 e-3   A
atomic unit of electric dipole mom.                         8.478 353 6198 e-30      0.000 000 0013 e-30      C m
atomic unit of electric field                               5.142 206 751 12 e11     0.000 000 000 80 e11     V m^-1
atomic unit of electric field gradient                      9.717 362 4424 e21       0.000 000 0030 e21       V m^-2
atomic unit of electric polarizability                      1.648 777 272 12 e-41    0.000 000 000 51 e-41    C^2 m^2 J^-1
atomic unit of electric potential                           27.211 386 245 981       0.000 000 000 030        V
atomic unit of electric quadrupole mom.                     4.486 551 5185 e-40      0.000 000 0014 e-40      C m^2
atomic unit of energy                                       4.359 744 722 2060 e-18  0.000 000 000 0048 e-18  J
atomic unit of force                                        8.238 723 5038 e-8       0.000 000 0013 e-8       N
atomic unit of length                                       5.291 772 105 44 e-11    0.000 000 000 82 e-11    m
atomic unit of mag. dipole mom.                             1.854 802 013 15 e-23    0.000 000 000 58 e-23    J T^-1
atomic unit of mag. flux density                            2.350 517 570 77 e5      0.000 000 000 73 e5      T
atomic unit of magnetizability                              7.891 036 5794 e-29      0.000 000 0049 e-29      J T^-2
atomic unit of mass                                         9.109 383 7139 e-31      0.000 000 0028 e-31      kg
atomic unit of momentum                                     1.992 851 915 45 e-24    0.000 000 000 31 e-24    kg m s^-1
atomic unit of permittivity                                 1.112 650 056 20 e-10    0.000 000 000 17 e-10    F m^-1
atomic unit of time                                         2.418 884 326 5864 e-17  0.000 000 000 0026 e-17  s
atomic unit of velocity                                     2.187 691 262 16 e6      0.000 000 000 34 e6      m s^-1
Avogadro constant                                           6.022 140 76 e23         (exact)                  mol^-1
Bohr magneton                                               9.274 010 0657 e-24      0.000 000 0029 e-24      J T^-1
Bohr magneton in eV/T                                       5.788 381 7982 e-5       0.000 000 0018 e-5       eV T^-1
Bohr magneton in Hz/T                                       1.399 624 491 71 e10     0.000 000 000 44 e10     Hz T^-1
Bohr magneton in inverse meter per tesla                    46.686 447 719           0.000 000 015            m^-1 T^-1
Bohr magneton in K/T                                        0.671 713 814 72         0.000 000 000 21         K T^-1
Bohr radius                                                 5.291 772 105 44 e-11    0.000 000 000 82 e-11    m
Boltzmann constant                                          1.380 649 e-23           (exact)                  J K^-1
Boltzmann constant in eV/K                                  8.617 333 262... e-5     (exact)                  eV K^-1
Boltzmann constant in Hz/K                                  2.083 661 912... e10     (exact)                  Hz K^-1
Boltzmann constant in inverse meter per kelvin              69.503 480 04...         (exact)                  m^-1 K^-1
characteristic impedance of vacuum                          376.730 313 412          0.000 000 059            ohm
classical electron radius                                   2.817 940 3205 e-15      0.000 000 0013 e-15      m
Compton wavelength                                          2.426 310 235 38 e-12    0.000 000 000 76 e-12    m
conductance quantum                                         7.748 091 729... e-5     (exact)                  S
conventional value of ampere-90                             1.000 000 088 87...      (exact)                  A
conventional value of coulomb-90                            1.000 000 088 87...      (exact)                  C
conventional value of farad-90                              0.999 999 982 20...      (exact)                  F
conventional value of henry-90                              1.000 000 017 79...      (exact)                  H
conventional value of Josephson constant                    483 597.9 e9             (exact)                  Hz V^-1
conventional value of ohm-90                                1.000 000 017 79...      (exact)                  ohm
conventional value of volt-90                               1.000 000 106 66...      (exact)                  V
conventional value of von Klitzing constant                 25 812.807               (exact)                  ohm
conventional value of watt-90                               1.000 000 195 53...      (exact)                  W
Copper x unit                                               1.002 076 97 e-13        0.000 000 28 e-13        m
deuteron-electron mag. mom. ratio                           -4.664 345 550 e-4       0.000 000 012 e-4        
deuteron-electron mass ratio                                3670.482 967 655         0.000 000 063            
deuteron g factor                                           0.857 438 2335           0.000 000 0022           
deuteron mag. mom.                                          4.330 735 087 e-27       0.000 000 011 e-27       J T^-1
deuteron mag. mom. to Bohr magneton ratio                   4.669 754 568 e-4        0.000 000 012 e-4        
deuteron mag. mom. to nuclear magneton ratio                0.857 438 2335           0.000 000 0022           
deuteron mass                                               3.343 583 7768 e-27      0.000 000 0010 e-27      kg
deuteron mass energy equivalent                             3.005 063 234 91 e-10    0.000 000 000 94 e-10    J
deuteron mass energy equivalent in MeV                      1875.612 945 00          0.000 000 58             MeV
deuteron mass in u                                          2.013 553 212 544        0.000 000 000 015        u
deuteron molar mass                                         2.013 553 214 66 e-3     0.000 000 000 63 e-3     kg mol^-1
deuteron-neutron mag. mom. ratio                            -0.448 206 52            0.000 000 11             
deuteron-proton mag. mom. ratio                             0.307 012 209 30         0.000 000 000 79         
deuteron-proton mass ratio                                  1.999 007 501 2699       0.000 000 000 0084       
deuteron relative atomic mass                               2.013 553 212 544        0.000 000 000 015        
deuteron rms charge radius                                  2.127 78 e-15            0.000 27 e-15            m
electron charge to mass quotient                            -1.758 820 008 38 e11    0.000 000 000 55 e11     C kg^-1
electron-deuteron mag. mom. ratio                           -2143.923 4921           0.000 0056               
electron-deuteron mass ratio                                2.724 437 107 629 e-4    0.000 000 000 047 e-4    
electron g factor                                           -2.002 319 304 360 92    0.000 000 000 000 36     
electron gyromag. ratio                                     1.760 859 627 84 e11     0.000 000 000 55 e11     s^-1 T^-1
electron gyromag. ratio in MHz/T                            28 024.951 3861          0.000 0087               MHz T^-1
electron-helion mass ratio                                  1.819 543 074 649 e-4    0.000 000 000 053 e-4    
electron mag. mom.                                          -9.284 764 6917 e-24     0.000 000 0029 e-24      J T^-1
electron mag. mom. anomaly                                  1.159 652 180 46 e-3     0.000 000 000 18 e-3     
electron mag. mom. to Bohr magneton ratio                   -1.001 159 652 180 46    0.000 000 000 000 18     
electron mag. mom. to nuclear magneton ratio                -1838.281 971 877        0.000 000 032            
electron mass                                               9.109 383 7139 e-31      0.000 000 0028 e-31      kg
electron mass energy equivalent                             8.187 105 7880 e-14      0.000 000 0026 e-14      J
electron mass energy equivalent in MeV                      0.510 998 950 69         0.000 000 000 16         MeV
electron mass in u                                          5.485 799 090 441 e-4    0.000 000 000 097 e-4    u
electron molar mass                                         5.485 799 0962 e-7       0.000 000 0017 e-7       kg mol^-1
electron-muon mag. mom. ratio                               206.766 9881             0.000 0046               
electron-muon mass ratio                                    4.836 331 70 e-3         0.000 000 11 e-3         
electron-neutron mag. mom. ratio                            960.920 48               0.000 23                 
electron-neutron mass ratio                                 5.438 673 4416 e-4       0.000 000 0022 e-4       
electron-proton mag. mom. ratio                             -658.210 687 89          0.000 000 19             
electron-proton mass ratio                                  5.446 170 214 889 e-4    0.000 000 000 094 e-4    
electron relative atomic mass                               5.485 799 090 441 e-4    0.000 000 000 097 e-4    
electron-tau mass ratio                                     2.875 85 e-4             0.000 19 e-4             
electron to alpha particle mass ratio                       1.370 933 554 733 e-4    0.000 000 000 032 e-4    
electron to shielded helion mag. mom. ratio                 864.058 239 86           0.000 000 70             
electron to shielded proton mag. mom. ratio                 -658.227 5856            0.000 0027               
electron-triton mass ratio                                  1.819 200 062 327 e-4    0.000 000 000 068 e-4    
electron volt                                               1.602 176 634 e-19       (exact)                  J
electron volt-atomic mass unit relationship                 1.073 544 100 83 e-9     0.000 000 000 33 e-9     u
electron volt-hartree relationship                          3.674 932 217 5665 e-2   0.000 000 000 0040 e-2   E_h
electron volt-hertz relationship                            2.417 989 242... e14     (exact)                  Hz
electron volt-inverse meter relationship                    8.065 543 937... e5      (exact)                  m^-1
electron volt-joule relationship                            1.602 176 634 e-19       (exact)                  J
electron volt-kelvin relationship                           1.160 451 812... e4      (exact)                  K
electron volt-kilogram relationship                         1.782 661 921... e-36    (exact)                  kg
elementary charge                                           1.602 176 634 e-19       (exact)                  C
elementary charge over h-bar                                1.519 267 447... e15     (exact)                  A J^-1
Faraday constant                                            96 485.332 12...         (exact)                  C mol^-1
Fermi coupling constant                                     1.166 3787 e-5           0.000 0006 e-5           GeV^-2
fine-structure constant                                     7.297 352 5643 e-3       0.000 000 0011 e-3       
first radiation constant                                    3.741 771 852... e-16    (exact)                  W m^2
first radiation constant for spectral radiance              1.191 042 972... e-16    (exact)                  W m^2 sr^-1
hartree-atomic mass unit relationship                       2.921 262 317 97 e-8     0.000 000 000 91 e-8     u
hartree-electron volt relationship                          27.211 386 245 981       0.000 000 000 030        eV
Hartree energy                                              4.359 744 722 2060 e-18  0.000 000 000 0048 e-18  J
Hartree energy in eV                                        27.211 386 245 981       0.000 000 000 030        eV
hartree-hertz relationship                                  6.579 683 920 4999 e15   0.000 000 000 0072 e15   Hz
hartree-inverse meter relationship                          2.194 746 313 6314 e7    0.000 000 000 0024 e7    m^-1
hartree-joule relationship                                  4.359 744 722 2060 e-18  0.000 000 000 0048 e-18  J
hartree-kelvin relationship                                 3.157 750 248 0398 e5    0.000 000 000 0034 e5    K
hartree-kilogram relationship                               4.850 870 209 5419 e-35  0.000 000 000 0053 e-35  kg
helion-electron mass ratio                                  5495.885 279 84          0.000 000 16             
helion g factor                                             -4.255 250 6995          0.000 000 0034           
helion mag. mom.                                            -1.074 617 551 98 e-26   0.000 000 000 93 e-26    J T^-1
helion mag. mom. to Bohr magneton ratio                     -1.158 740 980 83 e-3    0.000 000 000 94 e-3     
helion mag. mom. to nuclear magneton ratio                  -2.127 625 3498          0.000 000 0017           
helion mass                                                 5.006 412 7862 e-27      0.000 000 0016 e-27      kg
helion mass energy equivalent                               4.499 539 4185 e-10      0.000 000 0014 e-10      J
helion mass energy equivalent in MeV                        2808.391 611 12          0.000 000 88             MeV
helion mass in u                                            3.014 932 246 932        0.000 000 000 074        u
helion molar mass                                           3.014 932 250 10 e-3     0.000 000 000 94 e-3     kg mol^-1
helion-proton mass ratio                                    2.993 152 671 552        0.000 000 000 070        
helion relative atomic mass                                 3.014 932 246 932        0.000 000 000 074        
helion shielding shift                                      5.996 7029 e-5           0.000 0023 e-5           
hertz-atomic mass unit relationship                         4.439 821 6590 e-24      0.000 000 0014 e-24      u
hertz-electron volt relationship                            4.135 667 696... e-15    (exact)                  eV
hertz-hartree relationship                                  1.519 829 846 0574 e-16  0.000 000 000 0017 e-16  E_h
hertz-inverse meter relationship                            3.335 640 951... e-9     (exact)                  m^-1
hertz-joule relationship                                    6.626 070 15 e-34        (exact)                  J
hertz-kelvin relationship                                   4.799 243 073... e-11    (exact)                  K
hertz-kilogram relationship                                 7.372 497 323... e-51    (exact)                  kg
hyperfine transition frequency of Cs-133                    9 192 631 770            (exact)                  Hz
inverse fine-structure constant                             137.035 999 177          0.000 000 021            
inverse meter-atomic mass unit relationship                 1.331 025 048 24 e-15    0.000 000 000 41 e-15    u
inverse meter-electron volt relationship                    1.239 841 984... e-6     (exact)                  eV
inverse meter-hartree relationship                          4.556 335 252 9132 e-8   0.000 000 000 0050 e-8   E_h
inverse meter-hertz relationship                            299 792 458              (exact)                  Hz
inverse meter-joule relationship                            1.986 445 857... e-25    (exact)                  J
inverse meter-kelvin relationship                           1.438 776 877... e-2     (exact)                  K
inverse meter-kilogram relationship                         2.210 219 094... e-42    (exact)                  kg
inverse of conductance quantum                              12 906.403 72...         (exact)                  ohm
Josephson constant                                          483 597.848 4... e9      (exact)                  Hz V^-1
joule-atomic mass unit relationship                         6.700 535 2471 e9        0.000 000 0021 e9        u
joule-electron volt relationship                            6.241 509 074... e18     (exact)                  eV
joule-hartree relationship                                  2.293 712 278 3969 e17   0.000 000 000 0025 e17   E_h
joule-hertz relationship                                    1.509 190 179... e33     (exact)                  Hz
joule-inverse meter relationship                            5.034 116 567... e24     (exact)                  m^-1
joule-kelvin relationship                                   7.242 970 516... e22     (exact)                  K
joule-kilogram relationship                                 1.112 650 056... e-17    (exact)                  kg
kelvin-atomic mass unit relationship                        9.251 087 2884 e-14      0.000 000 0029 e-14      u
kelvin-electron volt relationship                           8.617 333 262... e-5     (exact)                  eV
kelvin-hartree relationship                                 3.166 811 563 4564 e-6   0.000 000 000 0035 e-6   E_h
kelvin-hertz relationship                                   2.083 661 912... e10     (exact)                  Hz
kelvin-inverse meter relationship                           69.503 480 04...         (exact)                  m^-1
kelvin-joule relationship                                   1.380 649 e-23           (exact)                  J
kelvin-kilogram relationship                                1.536 179 187... e-40    (exact)                  kg
kilogram-atomic mass unit relationship                      6.022 140 7537 e26       0.000 000 0019 e26       u
kilogram-electron volt relationship                         5.609 588 603... e35     (exact)                  eV
kilogram-hartree relationship                               2.061 485 788 7415 e34   0.000 000 000 0022 e34   E_h
kilogram-hertz relationship                                 1.356 392 489... e50     (exact)                  Hz
kilogram-inverse meter relationship                         4.524 438 335... e41     (exact)                  m^-1
kilogram-joule relationship                                 8.987 551 787... e16     (exact)                  J
kilogram-kelvin relationship                                6.509 657 260... e39     (exact)                  K
lattice parameter of silicon                                5.431 020 511 e-10       0.000 000 089 e-10       m
lattice spacing of ideal Si (220)                           1.920 155 716 e-10       0.000 000 032 e-10       m
Loschmidt constant (273.15 K, 100 kPa)                      2.651 645 804... e25     (exact)                  m^-3
Loschmidt constant (273.15 K, 101.325 kPa)                  2.686 780 111... e25     (exact)                  m^-3
luminous efficacy                                           683                      (exact)                  lm W^-1
mag. flux quantum                                           2.067 833 848... e-15    (exact)                  Wb
molar gas constant                                          8.314 462 618...         (exact)                  J mol^-1 K^-1
molar mass constant                                         1.000 000 001 05 e-3     0.000 000 000 31 e-3     kg mol^-1
molar mass of carbon-12                                     12.000 000 0126 e-3      0.000 000 0037 e-3       kg mol^-1
molar Planck constant                                       3.990 312 712... e-10    (exact)                  J Hz^-1 mol^-1
molar volume of ideal gas (273.15 K, 100 kPa)               22.710 954 64... e-3     (exact)                  m^3 mol^-1
molar volume of ideal gas (273.15 K, 101.325 kPa)           22.413 969 54... e-3     (exact)                  m^3 mol^-1
molar volume of silicon                                     1.205 883 199 e-5        0.000 000 060 e-5        m^3 mol^-1
Molybdenum x unit                                           1.002 099 52 e-13        0.000 000 53 e-13        m
muon Compton wavelength                                     1.173 444 110 e-14       0.000 000 026 e-14       m
muon-electron mass ratio                                    206.768 2827             0.000 0046               
muon g factor                                               -2.002 331 841 23        0.000 000 000 82         
muon mag. mom.                                              -4.490 448 30 e-26       0.000 000 10 e-26        J T^-1
muon mag. mom. anomaly                                      1.165 920 62 e-3         0.000 000 41 e-3         
muon mag. mom. to Bohr magneton ratio                       -4.841 970 48 e-3        0.000 000 11 e-3         
muon mag. mom. to nuclear magneton ratio                    -8.890 597 04            0.000 000 20             
muon mass                                                   1.883 531 627 e-28       0.000 000 042 e-28       kg
muon mass energy equivalent                                 1.692 833 804 e-11       0.000 000 038 e-11       J
muon mass energy equivalent in MeV                          105.658 3755             0.000 0023               MeV
muon mass in u                                              0.113 428 9257           0.000 000 0025           u
muon molar mass                                             1.134 289 258 e-4        0.000 000 025 e-4        kg mol^-1
muon-neutron mass ratio                                     0.112 454 5168           0.000 000 0025           
muon-proton mag. mom. ratio                                 -3.183 345 146           0.000 000 071            
muon-proton mass ratio                                      0.112 609 5262           0.000 000 0025           
muon-tau mass ratio                                         5.946 35 e-2             0.000 40 e-2             
natural unit of action                                      1.054 571 817... e-34    (exact)                  J s
natural unit of action in eV s                              6.582 119 569... e-16    (exact)                  eV s
natural unit of energy                                      8.187 105 7880 e-14      0.000 000 0026 e-14      J
natural unit of energy in MeV                               0.510 998 950 69         0.000 000 000 16         MeV
natural unit of length                                      3.861 592 6744 e-13      0.000 000 0012 e-13      m
natural unit of mass                                        9.109 383 7139 e-31      0.000 000 0028 e-31      kg
natural unit of momentum                                    2.730 924 534 46 e-22    0.000 000 000 85 e-22    kg m s^-1
natural unit of momentum in MeV/c                           0.510 998 950 69         0.000 000 000 16         MeV/c
natural unit of time                                        1.288 088 666 44 e-21    0.000 000 000 40 e-21    s
natural unit of velocity                                    299 792 458              (exact)                  m s^-1
neutron Compton wavelength                                  1.319 590 903 82 e-15    0.000 000 000 67 e-15    m
neutron-electron mag. mom. ratio                            1.040 668 84 e-3         0.000 000 24 e-3         
neutron-electron mass ratio                                 1838.683 662 00          0.000 000 74             
neutron g factor                                            -3.826 085 52            0.000 000 90             
neutron gyromag. ratio                                      1.832 471 74 e8          0.000 000 43 e8          s^-1 T^-1
neutron gyromag. ratio in MHz/T                             29.164 6935              0.000 0069               MHz T^-1
neutron mag. mom.                                           -9.662 3653 e-27         0.000 0023 e-27          J T^-1
neutron mag. mom. to Bohr magneton ratio                    -1.041 875 65 e-3        0.000 000 25 e-3         
neutron mag. mom. to nuclear magneton ratio                 -1.913 042 76            0.000 000 45             
neutron mass                                                1.674 927 500 56 e-27    0.000 000 000 85 e-27    kg
neutron mass energy equivalent                              1.505 349 765 14 e-10    0.000 000 000 76 e-10    J
neutron mass energy equivalent in MeV                       939.565 421 94           0.000 000 48             MeV
neutron mass in u                                           1.008 664 916 06         0.000 000 000 40         u
neutron molar mass                                          1.008 664 917 12 e-3     0.000 000 000 51 e-3     kg mol^-1
neutron-muon mass ratio                                     8.892 484 08             0.000 000 20             
neutron-proton mag. mom. ratio                              -0.684 979 35            0.000 000 16             
neutron-proton mass difference                              2.305 574 61 e-30        0.000 000 67 e-30        kg
neutron-proton mass difference energy equivalent            2.072 147 12 e-13        0.000 000 60 e-13        J
neutron-proton mass difference energy equivalent in MeV     1.293 332 51             0.000 000 38             MeV
neutron-proton mass difference in u                         1.388 449 48 e-3         0.000 000 40 e-3         u
neutron-proton mass ratio                                   1.001 378 419 46         0.000 000 000 40         
neutron relative atomic mass                                1.008 664 916 06         0.000 000 000 40         
neutron-tau mass ratio                                      0.528 779                0.000 036                
neutron to shielded proton mag. mom. ratio                  -0.684 996 94            0.000 000 16             
Newtonian constant of gravitation                           6.674 30 e-11            0.000 15 e-11            m^3 kg^-1 s^-2
Newtonian constant of gravitation over h-bar c              6.708 83 e-39            0.000 15 e-39            (GeV/c^2)^-2
nuclear magneton                                            5.050 783 7393 e-27      0.000 000 0016 e-27      J T^-1
nuclear magneton in eV/T                                    3.152 451 254 17 e-8     0.000 000 000 98 e-8     eV T^-1
nuclear magneton in inverse meter per tesla                 2.542 623 410 09 e-2     0.000 000 000 79 e-2     m^-1 T^-1
nuclear magneton in K/T                                     3.658 267 7706 e-4       0.000 000 0011 e-4       K T^-1
nuclear magneton in MHz/T                                   7.622 593 2188           0.000 000 0024           MHz T^-1
Planck constant                                             6.626 070 15 e-34        (exact)                  J Hz^-1
Planck constant in eV/Hz                                    4.135 667 696... e-15    (exact)                  eV Hz^-1
Planck length                                               1.616 255 e-35           0.000 018 e-35           m
Planck mass                                                 2.176 434 e-8            0.000 024 e-8            kg
Planck mass energy equivalent in GeV                        1.220 890 e19            0.000 014 e19            GeV
Planck temperature                                          1.416 784 e32            0.000 016 e32            K
Planck time                                                 5.391 247 e-44           0.000 060 e-44           s
proton charge to mass quotient                              9.578 833 1430 e7        0.000 000 0030 e7        C kg^-1
proton Compton wavelength                                   1.321 409 853 60 e-15    0.000 000 000 41 e-15    m
proton-electron mass ratio                                  1836.152 673 426         0.000 000 032            
proton g factor                                             5.585 694 6893           0.000 000 0016           
proton gyromag. ratio                                       2.675 221 8708 e8        0.000 000 0011 e8        s^-1 T^-1
proton gyromag. ratio in MHz/T                              42.577 478 461           0.000 000 018            MHz T^-1
proton mag. mom.                                            1.410 606 795 45 e-26    0.000 000 000 60 e-26    J T^-1
proton mag. mom. to Bohr magneton ratio                     1.521 032 202 30 e-3     0.000 000 000 45 e-3     
proton mag. mom. to nuclear magneton ratio                  2.792 847 344 63         0.000 000 000 82         
proton mag. shielding correction                            2.567 15 e-5             0.000 41 e-5             
proton mass                                                 1.672 621 925 95 e-27    0.000 000 000 52 e-27    kg
proton mass energy equivalent                               1.503 277 618 02 e-10    0.000 000 000 47 e-10    J
proton mass energy equivalent in MeV                        938.272 089 43           0.000 000 29             MeV
proton mass in u                                            1.007 276 466 5789       0.000 000 000 0083       u
proton molar mass                                           1.007 276 467 64 e-3     0.000 000 000 31 e-3     kg mol^-1
proton-muon mass ratio                                      8.880 243 38             0.000 000 20             
proton-neutron mag. mom. ratio                              -1.459 898 02            0.000 000 34             
proton-neutron mass ratio                                   0.998 623 477 97         0.000 000 000 40         
proton relative atomic mass                                 1.007 276 466 5789       0.000 000 000 0083       
proton rms charge radius                                    8.4075 e-16              0.0064 e-16              m
proton-tau mass ratio                                       0.528 051                0.000 036                
quantum of circulation                                      3.636 947 5467 e-4       0.000 000 0011 e-4       m^2 s^-1
quantum of circulation times 2                              7.273 895 0934 e-4       0.000 000 0023 e-4       m^2 s^-1
reduced Compton wavelength                                  3.861 592 6744 e-13      0.000 000 0012 e-13      m
reduced muon Compton wavelength                             1.867 594 306 e-15       0.000 000 042 e-15       m
reduced neutron Compton wavelength                          2.100 194 1520 e-16      0.000 000 0011 e-16      m
reduced Planck constant                                     1.054 571 817... e-34    (exact)                  J s
reduced Planck constant in eV s                             6.582 119 569... e-16    (exact)                  eV s
reduced Planck constant times c in MeV fm                   197.326 980 4...         (exact)                  MeV fm
reduced proton Compton wavelength                           2.103 089 100 51 e-16    0.000 000 000 66 e-16    m
reduced tau Compton wavelength                              1.110 538 e-16           0.000 075 e-16           m
Rydberg constant                                            10 973 731.568 157       0.000 012                m^-1
Rydberg constant times c in Hz                              3.289 841 960 2500 e15   0.000 000 000 0036 e15   Hz
Rydberg constant times hc in eV                             13.605 693 122 990       0.000 000 000 015        eV
Rydberg constant times hc in J                              2.179 872 361 1030 e-18  0.000 000 000 0024 e-18  J
Sackur-Tetrode constant (1 K, 100 kPa)                      -1.151 707 534 96        0.000 000 000 47         
Sackur-Tetrode constant (1 K, 101.325 kPa)                  -1.164 870 521 49        0.000 000 000 47         
second radiation constant                                   1.438 776 877... e-2     (exact)                  m K
shielded helion gyromag. ratio                              2.037 894 6078 e8        0.000 000 0018 e8        s^-1 T^-1
shielded helion gyromag. ratio in MHz/T                     32.434 100 033           0.000 000 028            MHz T^-1
shielded helion mag. mom.                                   -1.074 553 110 35 e-26   0.000 000 000 93 e-26    J T^-1
shielded helion mag. mom. to Bohr magneton ratio            -1.158 671 494 57 e-3    0.000 000 000 94 e-3     
shielded helion mag. mom. to nuclear magneton ratio         -2.127 497 7624          0.000 000 0017           
shielded helion to proton mag. mom. ratio                   -0.761 766 577 21        0.000 000 000 66         
shielded helion to shielded proton mag. mom. ratio          -0.761 786 1334          0.000 000 0031           
shielded proton gyromag. ratio                              2.675 153 194 e8         0.000 000 011 e8         s^-1 T^-1
shielded proton gyromag. ratio in MHz/T                     42.576 385 43            0.000 000 17             MHz T^-1
shielded proton mag. mom.                                   1.410 570 5830 e-26      0.000 000 0058 e-26      J T^-1
shielded proton mag. mom. to Bohr magneton ratio            1.520 993 1551 e-3       0.000 000 0062 e-3       
shielded proton mag. mom. to nuclear magneton ratio         2.792 775 648            0.000 000 011            
shielding difference of d and p in HD                       1.987 70 e-8             0.000 10 e-8             
shielding difference of t and p in HT                       2.394 50 e-8             0.000 20 e-8             
speed of light in vacuum                                    299 792 458              (exact)                  m s^-1
standard acceleration of gravity                            9.806 65                 (exact)                  m s^-2
standard atmosphere                                         101 325                  (exact)                  Pa
standard-state pressure                                     100 000                  (exact)                  Pa
Stefan-Boltzmann constant                                   5.670 374 419... e-8     (exact)                  W m^-2 K^-4
tau Compton wavelength                                      6.977 71 e-16            0.000 47 e-16            m
tau-electron mass ratio                                     3477.23                  0.23                     
tau energy equivalent                                       1776.86                  0.12                     MeV
tau mass                                                    3.167 54 e-27            0.000 21 e-27            kg
tau mass energy equivalent                                  2.846 84 e-10            0.000 19 e-10            J
tau mass in u                                               1.907 54                 0.000 13                 u
tau molar mass                                              1.907 54 e-3             0.000 13 e-3             kg mol^-1
tau-muon mass ratio                                         16.8170                  0.0011                   
tau-neutron mass ratio                                      1.891 15                 0.000 13                 
tau-proton mass ratio                                       1.893 76                 0.000 13                 
Thomson cross section                                       6.652 458 7051 e-29      0.000 000 0062 e-29      m^2
triton-electron mass ratio                                  5496.921 535 51          0.000 000 21             
triton g factor                                             5.957 924 930            0.000 000 012            
triton mag. mom.                                            1.504 609 5178 e-26      0.000 000 0030 e-26      J T^-1
triton mag. mom. to Bohr magneton ratio                     1.622 393 6648 e-3       0.000 000 0032 e-3       
triton mag. mom. to nuclear magneton ratio                  2.978 962 4650           0.000 000 0059           
triton mass                                                 5.007 356 7512 e-27      0.000 000 0016 e-27      kg
triton mass energy equivalent                               4.500 387 8119 e-10      0.000 000 0014 e-10      J
triton mass energy equivalent in MeV                        2808.921 136 68          0.000 000 88             MeV
triton mass in u                                            3.015 500 715 97         0.000 000 000 10         u
triton molar mass                                           3.015 500 719 13 e-3     0.000 000 000 94 e-3     kg mol^-1
triton-proton mass ratio                                    2.993 717 034 03         0.000 000 000 10         
triton relative atomic mass                                 3.015 500 715 97         0.000 000 000 10         
triton to proton mag. mom. ratio                            1.066 639 9189           0.000 000 0021           
unified atomic mass unit                                    1.660 539 068 92 e-27    0.000 000 000 52 e-27    kg
vacuum electric permittivity                                8.854 187 8188 e-12      0.000 000 0014 e-12      F m^-1
vacuum mag. permeability                                    1.256 637 061 27 e-6     0.000 000 000 20 e-6     N A^-2
von Klitzing constant                                       25 812.807 45...         (exact)                  ohm
weak mixing angle                                           0.223 05                 0.000 23                 
Wien frequency displacement law constant                    5.878 925 757... e10     (exact)                  Hz K^-1
Wien wavelength displacement law constant                   2.897 771 955... e-3     (exact)                  m K
W to Z mass ratio                                           0.881 45                 0.000 13                 


  Fundamental physical constants -- Complete Listing  2018 CODATA adjustment from http://physics.nist.gov.constants

  Quantity                                                       Value                 Uncertainty           Unit
-----------------------------------------------------------------------------------------------------------------------------
alpha particle-electron mass ratio                          7294.299 541 42          0.000 000 24             
alpha particle mass                                         6.644 657 3357 e-27      0.000 000 0020 e-27      kg
alpha particle mass energy equivalent                       5.971 920 1914 e-10      0.000 000 0018 e-10      J
alpha particle mass energy equivalent in MeV                3727.379 4066            0.000 0011               MeV
alpha particle mass in u                                    4.001 506 179 127        0.000 000 000 063        u
alpha particle molar mass                                   4.001 506 1777 e-3       0.000 000 0012 e-3       kg mol^-1
alpha particle-proton mass ratio                            3.972 599 690 09         0.000 000 000 22         
alpha particle relative atomic mass                         4.001 506 179 127        0.000 000 000 063        
Angstrom star                                               1.000 014 95 e-10        0.000 000 90 e-10        m
atomic mass constant                                        1.660 539 066 60 e-27    0.000 000 000 50 e-27    kg
atomic mass constant energy equivalent                      1.492 418 085 60 e-10    0.000 000 000 45 e-10    J
atomic mass constant energy equivalent in MeV               931.494 102 42           0.000 000 28             MeV
atomic mass unit-electron volt relationship                 9.314 941 0242 e8        0.000 000 0028 e8        eV
atomic mass unit-hartree relationship                       3.423 177 6874 e7        0.000 000 0010 e7        E_h
atomic mass unit-hertz relationship                         2.252 342 718 71 e23     0.000 000 000 68 e23     Hz
atomic mass unit-inverse meter relationship                 7.513 006 6104 e14       0.000 000 0023 e14       m^-1
atomic mass unit-joule relationship                         1.492 418 085 60 e-10    0.000 000 000 45 e-10    J
atomic mass unit-kelvin relationship                        1.080 954 019 16 e13     0.000 000 000 33 e13     K
atomic mass unit-kilogram relationship                      1.660 539 066 60 e-27    0.000 000 000 50 e-27    kg
atomic unit of 1st hyperpolarizability                      3.206 361 3061 e-53      0.000 000 0015 e-53      C^3 m^3 J^-2
atomic unit of 2nd hyperpolarizability                      6.235 379 9905 e-65      0.000 000 0038 e-65      C^4 m^4 J^-3
atomic unit of action                                       1.054 571 817... e-34    (exact)                  J s
atomic unit of charge                                       1.602 176 634 e-19       (exact)                  C
atomic unit of charge density                               1.081 202 384 57 e12     0.000 000 000 49 e12     C m^-3
atomic unit of current                                      6.623 618 237 510 e-3    0.000 000 000 013 e-3    A
atomic unit of electric dipole mom.                         8.478 353 6255 e-30      0.000 000 0013 e-30      C m
atomic unit of electric field                               5.142 206 747 63 e11     0.000 000 000 78 e11     V m^-1
atomic unit of electric field gradient                      9.717 362 4292 e21       0.000 000 0029 e21       V m^-2
atomic unit of electric polarizability                      1.648 777 274 36 e-41    0.000 000 000 50 e-41    C^2 m^2 J^-1
atomic unit of electric potential                           27.211 386 245 988       0.000 000 000 053        V
atomic unit of electric quadrupole mom.                     4.486 551 5246 e-40      0.000 000 0014 e-40      C m^2
atomic unit of energy                                       4.359 744 722 2071 e-18  0.000 000 000 0085 e-18  J
atomic unit of force                                        8.238 723 4983 e-8       0.000 000 0012 e-8       N
atomic unit of length                                       5.291 772 109 03 e-11    0.000 000 000 80 e-11    m
atomic unit of mag. dipole mom.                             1.854 802 015 66 e-23    0.000 000 000 56 e-23    J T^-1
atomic unit of mag. flux density                            2.350 517 567 58 e5      0.000 000 000 71 e5      T
atomic unit of magnetizability                              7.891 036 6008 e-29      0.000 000 0048 e-29      J T^-2
atomic unit of mass                                         9.109 383 7015 e-31      0.000 000 0028 e-31      kg
atomic unit of momentum                                     1.992 851 914 10 e-24    0.000 000 000 30 e-24    kg m s^-1
atomic unit of permittivity                                 1.112 650 055 45 e-10    0.000 000 000 17 e-10    F m^-1
atomic unit of time                                         2.418 884 326 5857 e-17  0.000 000 000 0047 e-17  s
atomic unit of velocity                                     2.187 691 263 64 e6      0.000 000 000 33 e6      m s^-1
Avogadro constant                                           6.022 140 76 e23         (exact)                  mol^-1
Bohr magneton                                               9.274 010 0783 e-24      0.000 000 0028 e-24      J T^-1
Bohr magneton in eV/T                                       5.788 381 8060 e-5       0.000 000 0017 e-5       eV T^-1
Bohr magneton in Hz/T                                       1.399 624 493 61 e10     0.000 000 000 42 e10     Hz T^-1
Bohr magneton in inverse meter per tesla                    46.686 447 783           0.000 000 014            m^-1 T^-1
Bohr magneton in K/T                                        0.671 713 815 63         0.000 000 000 20         K T^-1
Bohr radius                                                 5.291 772 109 03 e-11    0.000 000 000 80 e-11    m
Boltzmann constant                                          1.380 649 e-23           (exact)                  J K^-1
Boltzmann constant in eV/K                                  8.617 333 262... e-5     (exact)                  eV K^-1
Boltzmann constant in Hz/K                                  2.083 661 912... e10     (exact)                  Hz K^-1
Boltzmann constant in inverse meter per kelvin              69.503 480 04...         (exact)                  m^-1 K^-1
characteristic impedance of vacuum                          376.730 313 668          0.000 000 057            ohm
classical electron radius                                   2.817 940 3262 e-15      0.000 000 0013 e-15      m
Compton wavelength                                          2.426 310 238 67 e-12    0.000 000 000 73 e-12    m
conductance quantum                                         7.748 091 729... e-5     (exact)                  S
conventional value of ampere-90                             1.000 000 088 87...      (exact)                  A
conventional value of coulomb-90                            1.000 000 088 87...      (exact)                  C
conventional value of farad-90                              0.999 999 982 20...      (exact)                  F
conventional value of henry-90                              1.000 000 017 79...      (exact)                  H
conventional value of Josephson constant                    483 597.9 e9             (exact)                  Hz V^-1
conventional value of ohm-90                                1.000 000 017 79...      (exact)                  ohm
conventional value of volt-90                               1.000 000 106 66...      (exact)                  V
conventional value of von Klitzing constant                 25 812.807               (exact)                  ohm
conventional value of watt-90                               1.000 000 195 53...      (exact)                  W
Copper x unit                                               1.002 076 97 e-13        0.000 000 28 e-13        m
deuteron-electron mag. mom. ratio                           -4.664 345 551 e-4       0.000 000 012 e-4        
deuteron-electron mass ratio                                3670.482 967 88          0.000 000 13             
deuteron g factor                                           0.857 438 2338           0.000 000 0022           
deuteron mag. mom.                                          4.330 735 094 e-27       0.000 000 011 e-27       J T^-1
deuteron mag. mom. to Bohr magneton ratio                   4.669 754 570 e-4        0.000 000 012 e-4        
deuteron mag. mom. to nuclear magneton ratio                0.857 438 2338           0.000 000 0022           
deuteron mass                                               3.343 583 7724 e-27      0.000 000 0010 e-27      kg
deuteron mass energy equivalent                             3.005 063 231 02 e-10    0.000 000 000 91 e-10    J
deuteron mass energy equivalent in MeV                      1875.612 942 57          0.000 000 57             MeV
deuteron mass in u                                          2.013 553 212 745        0.000 000 000 040        u
deuteron molar mass                                         2.013 553 212 05 e-3     0.000 000 000 61 e-3     kg mol^-1
deuteron-neutron mag. mom. ratio                            -0.448 206 53            0.000 000 11             
deuteron-proton mag. mom. ratio                             0.307 012 209 39         0.000 000 000 79         
deuteron-proton mass ratio                                  1.999 007 501 39         0.000 000 000 11         
deuteron relative atomic mass                               2.013 553 212 745        0.000 000 000 040        
deuteron rms charge radius                                  2.127 99 e-15            0.000 74 e-15            m
electron charge to mass quotient                            -1.758 820 010 76 e11    0.000 000 000 53 e11     C kg^-1
electron-deuteron mag. mom. ratio                           -2143.923 4915           0.000 0056               
electron-deuteron mass ratio                                2.724 437 107 462 e-4    0.000 000 000 096 e-4    
electron g factor                                           -2.002 319 304 362 56    0.000 000 000 000 35     
electron gyromag. ratio                                     1.760 859 630 23 e11     0.000 000 000 53 e11     s^-1 T^-1
electron gyromag. ratio in MHz/T                            28 024.951 4242          0.000 0085               MHz T^-1
electron-helion mass ratio                                  1.819 543 074 573 e-4    0.000 000 000 079 e-4    
electron mag. mom.                                          -9.284 764 7043 e-24     0.000 000 0028 e-24      J T^-1
electron mag. mom. anomaly                                  1.159 652 181 28 e-3     0.000 000 000 18 e-3     
electron mag. mom. to Bohr magneton ratio                   -1.001 159 652 181 28    0.000 000 000 000 18     
electron mag. mom. to nuclear magneton ratio                -1838.281 971 88         0.000 000 11             
electron mass                                               9.109 383 7015 e-31      0.000 000 0028 e-31      kg
electron mass energy equivalent                             8.187 105 7769 e-14      0.000 000 0025 e-14      J
electron mass energy equivalent in MeV                      0.510 998 950 00         0.000 000 000 15         MeV
electron mass in u                                          5.485 799 090 65 e-4     0.000 000 000 16 e-4     u
electron molar mass                                         5.485 799 0888 e-7       0.000 000 0017 e-7       kg mol^-1
electron-muon mag. mom. ratio                               206.766 9883             0.000 0046               
electron-muon mass ratio                                    4.836 331 69 e-3         0.000 000 11 e-3         
electron-neutron mag. mom. ratio                            960.920 50               0.000 23                 
electron-neutron mass ratio                                 5.438 673 4424 e-4       0.000 000 0026 e-4       
electron-proton mag. mom. ratio                             -658.210 687 89          0.000 000 20             
electron-proton mass ratio                                  5.446 170 214 87 e-4     0.000 000 000 33 e-4     
electron relative atomic mass                               5.485 799 090 65 e-4     0.000 000 000 16 e-4     
electron-tau mass ratio                                     2.875 85 e-4             0.000 19 e-4             
electron to alpha particle mass ratio                       1.370 933 554 787 e-4    0.000 000 000 045 e-4    
electron to shielded helion mag. mom. ratio                 864.058 257              0.000 010                
electron to shielded proton mag. mom. ratio                 -658.227 5971            0.000 0072               
electron-triton mass ratio                                  1.819 200 062 251 e-4    0.000 000 000 090 e-4    
electron volt                                               1.602 176 634 e-19       (exact)                  J
electron volt-atomic mass unit relationship                 1.073 544 102 33 e-9     0.000 000 000 32 e-9     u
electron volt-hartree relationship                          3.674 932 217 5655 e-2   0.000 000 000 0071 e-2   E_h
electron volt-hertz relationship                            2.417 989 242... e14     (exact)                  Hz
electron volt-inverse meter relationship                    8.065 543 937... e5      (exact)                  m^-1
electron volt-joule relationship                            1.602 176 634 e-19       (exact)                  J
electron volt-kelvin relationship                           1.160 451 812... e4      (exact)                  K
electron volt-kilogram relationship                         1.782 661 921... e-36    (exact)                  kg
elementary charge                                           1.602 176 634 e-19       (exact)                  C
elementary charge over h-bar                                1.519 267 447... e15     (exact)                  A J^-1
Faraday constant                                            96 485.332 12...         (exact)                  C mol^-1
Fermi coupling constant                                     1.166 3787 e-5           0.000 0006 e-5           GeV^-2
fine-structure constant                                     7.297 352 5693 e-3       0.000 000 0011 e-3       
first radiation constant                                    3.741 771 852... e-16    (exact)                  W m^2
first radiation constant for spectral radiance              1.191 042 972... e-16    (exact)                  W m^2 sr^-1
hartree-atomic mass unit relationship                       2.921 262 322 05 e-8     0.000 000 000 88 e-8     u
hartree-electron volt relationship                          27.211 386 245 988       0.000 000 000 053        eV
Hartree energy                                              4.359 744 722 2071 e-18  0.000 000 000 0085 e-18  J
Hartree energy in eV                                        27.211 386 245 988       0.000 000 000 053        eV
hartree-hertz relationship                                  6.579 683 920 502 e15    0.000 000 000 013 e15    Hz
hartree-inverse meter relationship                          2.194 746 313 6320 e7    0.000 000 000 0043 e7    m^-1
hartree-joule relationship                                  4.359 744 722 2071 e-18  0.000 000 000 0085 e-18  J
hartree-kelvin relationship                                 3.157 750 248 0407 e5    0.000 000 000 0061 e5    K
hartree-kilogram relationship                               4.850 870 209 5432 e-35  0.000 000 000 0094 e-35  kg
helion-electron mass ratio                                  5495.885 280 07          0.000 000 24             
helion g factor                                             -4.255 250 615           0.000 000 050            
helion mag. mom.                                            -1.074 617 532 e-26      0.000 000 013 e-26       J T^-1
helion mag. mom. to Bohr magneton ratio                     -1.158 740 958 e-3       0.000 000 014 e-3        
helion mag. mom. to nuclear magneton ratio                  -2.127 625 307           0.000 000 025            
helion mass                                                 5.006 412 7796 e-27      0.000 000 0015 e-27      kg
helion mass energy equivalent                               4.499 539 4125 e-10      0.000 000 0014 e-10      J
helion mass energy equivalent in MeV                        2808.391 607 43          0.000 000 85             MeV
helion mass in u                                            3.014 932 247 175        0.000 000 000 097        u
helion molar mass                                           3.014 932 246 13 e-3     0.000 000 000 91 e-3     kg mol^-1
helion-proton mass ratio                                    2.993 152 671 67         0.000 000 000 13         
helion relative atomic mass                                 3.014 932 247 175        0.000 000 000 097        
helion shielding shift                                      5.996 743 e-5            0.000 010 e-5            
hertz-atomic mass unit relationship                         4.439 821 6652 e-24      0.000 000 0013 e-24      u
hertz-electron volt relationship                            4.135 667 696... e-15    (exact)                  eV
hertz-hartree relationship                                  1.519 829 846 0570 e-16  0.000 000 000 0029 e-16  E_h
hertz-inverse meter relationship                            3.335 640 951... e-9     (exact)                  m^-1
hertz-joule relationship                                    6.626 070 15 e-34        (exact)                  J
hertz-kelvin relationship                                   4.799 243 073... e-11    (exact)                  K
hertz-kilogram relationship                                 7.372 497 323... e-51    (exact)                  kg
hyperfine transition frequency of Cs-133                    9 192 631 770            (exact)                  Hz
inverse fine-structure constant                             137.035 999 084          0.000 000 021            
inverse meter-atomic mass unit relationship                 1.331 025 050 10 e-15    0.000 000 000 40 e-15    u
inverse meter-electron volt relationship                    1.239 841 984... e-6     (exact)                  eV
inverse meter-hartree relationship                          4.556 335 252 9120 e-8   0.000 000 000 0088 e-8   E_h
inverse meter-hertz relationship                            299 792 458              (exact)                  Hz
inverse meter-joule relationship                            1.986 445 857... e-25    (exact)                  J
inverse meter-kelvin relationship                           1.438 776 877... e-2     (exact)                  K
inverse meter-kilogram relationship                         2.210 219 094... e-42    (exact)                  kg
inverse of conductance quantum                              12 906.403 72...         (exact)                  ohm
Josephson constant                                          483 597.848 4... e9      (exact)                  Hz V^-1
joule-atomic mass unit relationship                         6.700 535 2565 e9        0.000 000 0020 e9        u
joule-electron volt relationship                            6.241 509 074... e18     (exact)                  eV
joule-hartree relationship                                  2.293 712 278 3963 e17   0.000 000 000 0045 e17   E_h
joule-hertz relationship                                    1.509 190 179... e33     (exact)                  Hz
joule-inverse meter relationship                            5.034 116 567... e24     (exact)                  m^-1
joule-kelvin relationship                                   7.242 970 516... e22     (exact)                  K
joule-kilogram relationship                                 1.112 650 056... e-17    (exact)                  kg
kelvin-atomic mass unit relationship                        9.251 087 3014 e-14      0.000 000 0028 e-14      u
kelvin-electron volt relationship                           8.617 333 262... e-5     (exact)                  eV
kelvin-hartree relationship                                 3.166 811 563 4556 e-6   0.000 000 000 0061 e-6   E_h
kelvin-hertz relationship                                   2.083 661 912... e10     (exact)                  Hz
kelvin-inverse meter relationship                           69.503 480 04...         (exact)                  m^-1
kelvin-joule relationship                                   1.380 649 e-23           (exact)                  J
kelvin-kilogram relationship                                1.536 179 187... e-40    (exact)                  kg
kilogram-atomic mass unit relationship                      6.022 140 7621 e26       0.000 000 0018 e26       u
kilogram-electron volt relationship                         5.609 588 603... e35     (exact)                  eV
kilogram-hartree relationship                               2.061 485 788 7409 e34   0.000 000 000 0040 e34   E_h
kilogram-hertz relationship                                 1.356 392 489... e50     (exact)                  Hz
kilogram-inverse meter relationship                         4.524 438 335... e41     (exact)                  m^-1
kilogram-joule relationship                                 8.987 551 787... e16     (exact)                  J
kilogram-kelvin relationship                                6.509 657 260... e39     (exact)                  K
lattice parameter of silicon                                5.431 020 511 e-10       0.000 000 089 e-10       m
lattice spacing of ideal Si (220)                           1.920 155 716 e-10       0.000 000 032 e-10       m
Loschmidt constant (273.15 K, 100 kPa)                      2.651 645 804... e25     (exact)                  m^-3
Loschmidt constant (273.15 K, 101.325 kPa)                  2.686 780 111... e25     (exact)                  m^-3
luminous efficacy                                           683                      (exact)                  lm W^-1
mag. flux quantum                                           2.067 833 848... e-15    (exact)                  Wb
molar gas constant                                          8.314 462 618...         (exact)                  J mol^-1 K^-1
molar mass constant                                         0.999 999 999 65 e-3     0.000 000 000 30 e-3     kg mol^-1
molar mass of carbon-12                                     11.999 999 9958 e-3      0.000 000 0036 e-3       kg mol^-1
molar Planck constant                                       3.990 312 712... e-10    (exact)                  J Hz^-1 mol^-1
molar volume of ideal gas (273.15 K, 100 kPa)               22.710 954 64... e-3     (exact)                  m^3 mol^-1
molar volume of ideal gas (273.15 K, 101.325 kPa)           22.413 969 54... e-3     (exact)                  m^3 mol^-1
molar volume of silicon                                     1.205 883 199 e-5        0.000 000 060 e-5        m^3 mol^-1
Molybdenum x unit                                           1.002 099 52 e-13        0.000 000 53 e-13        m
muon Compton wavelength                                     1.173 444 110 e-14       0.000 000 026 e-14       m
muon-electron mass ratio                                    206.768 2830             0.000 0046               
muon g factor                                               -2.002 331 8418          0.000 000 0013           
muon mag. mom.                                              -4.490 448 30 e-26       0.000 000 10 e-26        J T^-1
muon mag. mom. anomaly                                      1.165 920 89 e-3         0.000 000 63 e-3         
muon mag. mom. to Bohr magneton ratio                       -4.841 970 47 e-3        0.000 000 11 e-3         
muon mag. mom. to nuclear magneton ratio                    -8.890 597 03            0.000 000 20             
muon mass                                                   1.883 531 627 e-28       0.000 000 042 e-28       kg
muon mass energy equivalent                                 1.692 833 804 e-11       0.000 000 038 e-11       J
muon mass energy equivalent in MeV                          105.658 3755             0.000 0023               MeV
muon mass in u                                              0.113 428 9259           0.000 000 0025           u
muon molar mass                                             1.134 289 259 e-4        0.000 000 025 e-4        kg mol^-1
muon-neutron mass ratio                                     0.112 454 5170           0.000 000 0025           
muon-proton mag. mom. ratio                                 -3.183 345 142           0.000 000 071            
muon-proton mass ratio                                      0.112 609 5264           0.000 000 0025           
muon-tau mass ratio                                         5.946 35 e-2             0.000 40 e-2             
natural unit of action                                      1.054 571 817... e-34    (exact)                  J s
natural unit of action in eV s                              6.582 119 569... e-16    (exact)                  eV s
natural unit of energy                                      8.187 105 7769 e-14      0.000 000 0025 e-14      J
natural unit of energy in MeV                               0.510 998 950 00         0.000 000 000 15         MeV
natural unit of length                                      3.861 592 6796 e-13      0.000 000 0012 e-13      m
natural unit of mass                                        9.109 383 7015 e-31      0.000 000 0028 e-31      kg
natural unit of momentum                                    2.730 924 530 75 e-22    0.000 000 000 82 e-22    kg m s^-1
natural unit of momentum in MeV/c                           0.510 998 950 00         0.000 000 000 15         MeV/c
natural unit of time                                        1.288 088 668 19 e-21    0.000 000 000 39 e-21    s
natural unit of velocity                                    299 792 458              (exact)                  m s^-1
neutron Compton wavelength                                  1.319 590 905 81 e-15    0.000 000 000 75 e-15    m
neutron-electron mag. mom. ratio                            1.040 668 82 e-3         0.000 000 25 e-3         
neutron-electron mass ratio                                 1838.683 661 73          0.000 000 89             
neutron g factor                                            -3.826 085 45            0.000 000 90             
neutron gyromag. ratio                                      1.832 471 71 e8          0.000 000 43 e8          s^-1 T^-1
neutron gyromag. ratio in MHz/T                             29.164 6931              0.000 0069               MHz T^-1
neutron mag. mom.                                           -9.662 3651 e-27         0.000 0023 e-27          J T^-1
neutron mag. mom. to Bohr magneton ratio                    -1.041 875 63 e-3        0.000 000 25 e-3         
neutron mag. mom. to nuclear magneton ratio                 -1.913 042 73            0.000 000 45             
neutron mass                                                1.674 927 498 04 e-27    0.000 000 000 95 e-27    kg
neutron mass energy equivalent                              1.505 349 762 87 e-10    0.000 000 000 86 e-10    J
neutron mass energy equivalent in MeV                       939.565 420 52           0.000 000 54             MeV
neutron mass in u                                           1.008 664 915 95         0.000 000 000 49         u
neutron molar mass                                          1.008 664 915 60 e-3     0.000 000 000 57 e-3     kg mol^-1
neutron-muon mass ratio                                     8.892 484 06             0.000 000 20             
neutron-proton mag. mom. ratio                              -0.684 979 34            0.000 000 16             
neutron-proton mass difference                              2.305 574 35 e-30        0.000 000 82 e-30        kg
neutron-proton mass difference energy equivalent            2.072 146 89 e-13        0.000 000 74 e-13        J
neutron-proton mass difference energy equivalent in MeV     1.293 332 36             0.000 000 46             MeV
neutron-proton mass difference in u                         1.388 449 33 e-3         0.000 000 49 e-3         u
neutron-proton mass ratio                                   1.001 378 419 31         0.000 000 000 49         
neutron relative atomic mass                                1.008 664 915 95         0.000 000 000 49         
neutron-tau mass ratio                                      0.528 779                0.000 036                
neutron to shielded proton mag. mom. ratio                  -0.684 996 94            0.000 000 16             
Newtonian constant of gravitation                           6.674 30 e-11            0.000 15 e-11            m^3 kg^-1 s^-2
Newtonian constant of gravitation over h-bar c              6.708 83 e-39            0.000 15 e-39            (GeV/c^2)^-2
nuclear magneton                                            5.050 783 7461 e-27      0.000 000 0015 e-27      J T^-1
nuclear magneton in eV/T                                    3.152 451 258 44 e-8     0.000 000 000 96 e-8     eV T^-1
nuclear magneton in inverse meter per tesla                 2.542 623 413 53 e-2     0.000 000 000 78 e-2     m^-1 T^-1
nuclear magneton in K/T                                     3.658 267 7756 e-4       0.000 000 0011 e-4       K T^-1
nuclear magneton in MHz/T                                   7.622 593 2291           0.000 000 0023           MHz T^-1
Planck constant                                             6.626 070 15 e-34        (exact)                  J Hz^-1
Planck constant in eV/Hz                                    4.135 667 696... e-15    (exact)                  eV Hz^-1
Planck length                                               1.616 255 e-35           0.000 018 e-35           m
Planck mass                                                 2.176 434 e-8            0.000 024 e-8            kg
Planck mass energy equivalent in GeV                        1.220 890 e19            0.000 014 e19            GeV
Planck temperature                                          1.416 784 e32            0.000 016 e32            K
Planck time                                                 5.391 247 e-44           0.000 060 e-44           s
proton charge to mass quotient                              9.578 833 1560 e7        0.000 000 0029 e7        C kg^-1
proton Compton wavelength                                   1.321 409 855 39 e-15    0.000 000 000 40 e-15    m
proton-electron mass ratio                                  1836.152 673 43          0.000 000 11             
proton g factor                                             5.585 694 6893           0.000 000 0016           
proton gyromag. ratio                                       2.675 221 8744 e8        0.000 000 0011 e8        s^-1 T^-1
proton gyromag. ratio in MHz/T                              42.577 478 518           0.000 000 018            MHz T^-1
proton mag. mom.                                            1.410 606 797 36 e-26    0.000 000 000 60 e-26    J T^-1
proton mag. mom. to Bohr magneton ratio                     1.521 032 202 30 e-3     0.000 000 000 46 e-3     
proton mag. mom. to nuclear magneton ratio                  2.792 847 344 63         0.000 000 000 82         
proton mag. shielding correction                            2.5689 e-5               0.0011 e-5               
proton mass                                                 1.672 621 923 69 e-27    0.000 000 000 51 e-27    kg
proton mass energy equivalent                               1.503 277 615 98 e-10    0.000 000 000 46 e-10    J
proton mass energy equivalent in MeV                        938.272 088 16           0.000 000 29             MeV
proton mass in u                                            1.007 276 466 621        0.000 000 000 053        u
proton molar mass                                           1.007 276 466 27 e-3     0.000 000 000 31 e-3     kg mol^-1
proton-muon mass ratio                                      8.880 243 37             0.000 000 20             
proton-neutron mag. mom. ratio                              -1.459 898 05            0.000 000 34             
proton-neutron mass ratio                                   0.998 623 478 12         0.000 000 000 49         
proton relative atomic mass                                 1.007 276 466 621        0.000 000 000 053        
proton rms charge radius                                    8.414 e-16               0.019 e-16               m
proton-tau mass ratio                                       0.528 051                0.000 036                
quantum of circulation                                      3.636 947 5516 e-4       0.000 000 0011 e-4       m^2 s^-1
quantum of circulation times 2                              7.273 895 1032 e-4       0.000 000 0022 e-4       m^2 s^-1
reduced Compton wavelength                                  3.861 592 6796 e-13      0.000 000 0012 e-13      m
reduced muon Compton wavelength                             1.867 594 306 e-15       0.000 000 042 e-15       m
reduced neutron Compton wavelength                          2.100 194 1552 e-16      0.000 000 0012 e-16      m
reduced Planck constant                                     1.054 571 817... e-34    (exact)                  J s
reduced Planck constant in eV s                             6.582 119 569... e-16    (exact)                  eV s
reduced Planck constant times c in MeV fm                   197.326 980 4...         (exact)                  MeV fm
reduced proton Compton wavelength                           2.103 089 103 36 e-16    0.000 000 000 64 e-16    m
reduced tau Compton wavelength                              1.110 538 e-16           0.000 075 e-16           m
Rydberg constant                                            10 973 731.568 160       0.000 021                m^-1
Rydberg constant times c in Hz                              3.289 841 960 2508 e15   0.000 000 000 0064 e15   Hz
Rydberg constant times hc in eV                             13.605 693 122 994       0.000 000 000 026        eV
Rydberg constant times hc in J                              2.179 872 361 1035 e-18  0.000 000 000 0042 e-18  J
Sackur-Tetrode constant (1 K, 100 kPa)                      -1.151 707 537 06        0.000 000 000 45         
Sackur-Tetrode constant (1 K, 101.325 kPa)                  -1.164 870 523 58        0.000 000 000 45         
second radiation constant                                   1.438 776 877... e-2     (exact)                  m K
shielded helion gyromag. ratio                              2.037 894 569 e8         0.000 000 024 e8         s^-1 T^-1
shielded helion gyromag. ratio in MHz/T                     32.434 099 42            0.000 000 38             MHz T^-1
shielded helion mag. mom.                                   -1.074 553 090 e-26      0.000 000 013 e-26       J T^-1
shielded helion mag. mom. to Bohr magneton ratio            -1.158 671 471 e-3       0.000 000 014 e-3        
shielded helion mag. mom. to nuclear magneton ratio         -2.127 497 719           0.000 000 025            
shielded helion to proton mag. mom. ratio                   -0.761 766 5618          0.000 000 0089           
shielded helion to shielded proton mag. mom. ratio          -0.761 786 1313          0.000 000 0033           
shielded proton gyromag. ratio                              2.675 153 151 e8         0.000 000 029 e8         s^-1 T^-1
shielded proton gyromag. ratio in MHz/T                     42.576 384 74            0.000 000 46             MHz T^-1
shielded proton mag. mom.                                   1.410 570 560 e-26       0.000 000 015 e-26       J T^-1
shielded proton mag. mom. to Bohr magneton ratio            1.520 993 128 e-3        0.000 000 017 e-3        
shielded proton mag. mom. to nuclear magneton ratio         2.792 775 599            0.000 000 030            
shielding difference of d and p in HD                       2.0200 e-8               0.0020 e-8               
shielding difference of t and p in HT                       2.4140 e-8               0.0020 e-8               
speed of light in vacuum                                    299 792 458              (exact)                  m s^-1
standard acceleration of gravity                            9.806 65                 (exact)                  m s^-2
standard atmosphere                                         101 325                  (exact)                  Pa
standard-state pressure                                     100 000                  (exact)                  Pa
Stefan-Boltzmann constant                                   5.670 374 419... e-8     (exact)                  W m^-2 K^-4
tau Compton wavelength                                      6.977 71 e-16            0.000 47 e-16            m
tau-electron mass ratio                                     3477.23                  0.23                     
tau energy equivalent                                       1776.86                  0.12                     MeV
tau mass                                                    3.167 54 e-27            0.000 21 e-27            kg
tau mass energy equivalent                                  2.846 84 e-10            0.000 19 e-10            J
tau mass in u                                               1.907 54                 0.000 13                 u
tau molar mass                                              1.907 54 e-3             0.000 13 e-3             kg mol^-1
tau-muon mass ratio                                         16.8170                  0.0011                   
tau-neutron mass ratio                                      1.891 15                 0.000 13                 
tau-proton mass ratio                                       1.893 76                 0.000 13                 
Thomson cross section                                       6.652 458 7321 e-29      0.000 000 0060 e-29      m^2
triton-electron mass ratio                                  5496.921 535 73          0.000 000 27             
triton g factor                                             5.957 924 931            0.000 000 012            
triton mag. mom.                                            1.504 609 5202 e-26      0.000 000 0030 e-26      J T^-1
triton mag. mom. to Bohr magneton ratio                     1.622 393 6651 e-3       0.000 000 0032 e-3       
triton mag. mom. to nuclear magneton ratio                  2.978 962 4656           0.000 000 0059           
triton mass                                                 5.007 356 7446 e-27      0.000 000 0015 e-27      kg
triton mass energy equivalent                               4.500 387 8060 e-10      0.000 000 0014 e-10      J
triton mass energy equivalent in MeV                        2808.921 132 98          0.000 000 85             MeV
triton mass in u                                            3.015 500 716 21         0.000 000 000 12         u
triton molar mass                                           3.015 500 715 17 e-3     0.000 000 000 92 e-3     kg mol^-1
triton-proton mass ratio                                    2.993 717 034 14         0.000 000 000 15         
triton relative atomic mass                                 3.015 500 716 21         0.000 000 000 12         
triton to proton mag. mom. ratio                            1.066 639 9191           0.000 000 0021           
unified atomic mass unit                                    1.660 539 066 60 e-27    0.000 000 000 50 e-27    kg
vacuum electric permittivity                                8.854 187 8128 e-12      0.000 000 0013 e-12      F m^-1
vacuum mag. permeability                                    1.256 637 062 12 e-6     0.000 000 000 19 e-6     N A^-2
von Klitzing constant                                       25 812.807 45...         (exact)                  ohm
weak mixing angle                                           0.222 90                 0.000 30                 
Wien frequency displacement law constant                    5.878 925 757... e10     (exact)                  Hz K^-1
Wien wavelength displacement law constant                   2.897 771 955... e-3     (exact)                  m K
W to Z mass ratio                                           0.881 53                 0.000 17