Relativity Science Calculator - Fundamental Constants

Fundamental Physical Constants --- CODATA 2016 Listing

Quantity Symbol Value Unit
alpha particle-electron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 7294.299 5365(31)
alpha particle mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.644 656 20(33) x 10-27 kg
alpha particle mass energy equivalent Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.971 919 17(30) x 10-10 J
alpha particle mass energy equivalent in MeV Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3727.379 109(93) MeV
alpha particle mass in u Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.001 506 179 127(62) u
alpha particle molar mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.001 506 179 127(62) x 10-3 kg mol-1
alpha particle-proton mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.972 599 689 51(41)
Angstrom star Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.000 014 98(90) x 10-10 m
atomic mass constant Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.660 538 782(83) x 10-27 kg
atomic mass constant energy equivalent Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.492 417 830(74) x 10-10 J
atomic mass constant energy equivalent in MeV Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 931.494 028(23) MeV
atomic mass unit-electron volt relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 931.494 028(23) x 106 eV
atomic unit of mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 9.109 382 15(45) x 10-31 kg
atomic mass unit-kilogram relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.660 538 782(83) x 10-27 kg
atomic unit of action ( Dirac's Constant ) Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.054 571 628(53) x 10-34 J s
atomic unit of charge ( elementary charge ) Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.602 176 487(40) x 10-19 C
atomic unit of charge density Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.081 202 300(27) x 1012 C m-3
atomic unit of current Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.623 617 63(17) x 10-3 A
atomic unit of electric dipole moment Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 8.478 352 81(21) x 10-30 C m
atomic unit of electric field Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.142 206 32(13) x 1011 V m-1
atomic unit of electric field gradient Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 9.717 361 66(24) x 1021 V m-2
atomic unit of electric polarizablity Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.648 777 2536(34) x 10-41 C2 m2 J-1
atomic unit of electric potential Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 27.211 383 86(68) V
atomic unit of electric quadrupole moment Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.486 551 07(11) x 10-40 C m2
atomic unit of energy Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.359 743 94(22) x 10-18 J
atomic unit of force Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 8.238 722 06(41) x 10-8 N
atomic unit of length Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.529 177 208 59(36) x 10-10 m
atomic unit of mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 9.109 382 15(45) x 10-31 kg
atomic unit of momentum Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.992 851 565(99) x 10-24 kg m s-1
atomic unit of permittivity Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.112 650 056... x 10-10 F m-1
atomic unit of time Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.418 884 326 505(16) x 10-17 s
atomic unit of velocity Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.187 691 2541(15) x 106 m s-1
Avogadro constant, number Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.022 141 79(30) x 1023 mol-1
Bohr magneton Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 927.400 915(23) x 10-26 J T-1
Bohr magneton in eV/T Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.788 381 7555(79) x 10-5 eV T-1
Bohr magneton in Hz/T Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 13.996 246 04(35) x 109 Hz T-1
Bohr magneton in inverse meters per tesla Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 46.686 4515(12) m-1 T-1
Bohr magneton in K/T Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.671 7131(12) K T-1
Bohr radius Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.529 177 208 59(36) x 10-10 m
Boltzmann Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.380 6504(24) x 10-23 J K-1
Boltzmann constant in eV/K Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 8.617 343(15) x 10-5 eV K-1
Boltzmann constant in Hz/K Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.083 6644(36) x 1010 Hz K-1
Boltzmann constant in inverse meters per kelvin Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 69.503 56(12) m-1 K-1
characteristic impedance of vacuum Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 376.730 313 461... Ω
classical electron radius Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.817 940 2894(58) x 10-15 m
Coulomb ( force ) constant Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 8.987 551 787 4 x 109 N m2 C-2
Compton wavelength Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.426 310 2175(33) x 10-12 m
Compton wavelength over 2 pi Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 386.159 264 59(53) x 10-15 m
conductance quantum Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 7.748 091 7004(53) x 10-5 S
deuteron-electron magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -4.664 345 537(39) x 10-4
deuteron-electron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3670.482 9654(16)
deuteron g factor Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.857 438 2308(72)
deuteron mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.343 583 20(17) x 10-27 kg
deuteron mass energy equivalent Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.005 062 72(15) x 10-10 J
deuteron mass energy equivalent in MeV Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1875.612 793(47) MeV
deuteron mass in u Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.013 553 212 724(78) u
deuteron molar mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.013 553 212 724(78) x 10-3 kg mol-1
deuteron-electron magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -4.664 345 537(39) x 10-4
deuteron-neutron magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -0.448 206 52(11)
deuteron-proton magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.307 012 2070(24)
deuteron-proton mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.999 007 501 08(22)
Dirac's Constant Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.054 571 628(53) x 10-34 J s
electric constant ( vacuum permittivity ) Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 8.854 187 817... x 10-12 F m-1
electron charge to mass quotient Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -1.758 820 150(44) x 1011 C kg-1
electron-deuteron magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -2143.923 498(18)
electron-deuteron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.724 437 1093(12) x 10-4
electron g factor Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -2.002 319 304 3622(15)
electron mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 9.109 382 15(45) x 10-31 kg
electron mass energy equivalent Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 8.187 104 38(41) x 10-14 J
electron mass energy equivalent in MeV Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.510 998 910(13) MeV
electron mass in u Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.485 799 0943(23) x 10-4 u
electron molar mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.485 799 0943(23) x 10-7 kg mol-1
electron-muon magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 206.766 9877(52)
electron-muon mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.836 331 71(12) x 10-3
electron-neutron magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 960.920 50(23)
electron-neutron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.438 673 4459(33) x 10-4
electron-proton magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -658.210 6848(54)
electron-proton mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.446 170 2177(24) x 10-4
electron-tau mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.875 64(47) x 10-4
electron to alpha particle mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.370 933 555 70(58) x 10-4
electron volt Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.602 176 487(40) x 10-19 J
electron volt-atomic mass unit relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.073 544 188(27) x 10-9 u
electron volt-hartree relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.674 932 540(92) x 10-2 Eh
electron volt-hertz relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.417 989 454(60) x 1014 Hz
electron volt-inverse meter relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 8.065 544 65(20) x 105 m-1
electron volt-joule relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.602 176 487(40) x 10-19 J
electron volt-kelvin relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.160 4505(20) x 104 K
electron volt-kilogram relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.782 661 758(44) x 10-36 kg
elementary charge Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.602 176 487(40) x 10-19 C
elementary charge over h Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.417 989 454(60) x 1014 A J-1
Faraday constant Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 96 485.3399(24) C mol-1
Faraday constant for conventional electric current Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 96 485.3401(48) C90 mol-1
Fermi coupling constant Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.166 37(1) x 10-5 GeV-2
fine-structure constant Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 7.297 352 5376(50) x 10-3
helion-electron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5495.885 2765(52)
helion mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.006 411 92(25) x 10-27 kg
helion mass energy equivalent Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.499 538 64(22) x 10-10 J
helion mass energy equivalent in MeV Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2808.391 383(70) MeV
helion mass in u Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.014 932 2473(26) u
helion molar mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.014 932 2473(26) x 10-3 kg mol-1
helion-proton mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.993 152 6713(26)
hertz-atomic mass unit relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.439 821 6294(64) x 10-24 u
hertz-electron volt relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.135 667 33(10) x 10-15 eV
hertz-hartree relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.519 829 846 006(10) x 10-16 Eh
hertz-inverse meter relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.335 640 951ldots x 10-9 m-1
hertz-joule relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.626 068 96(33) x 10-34 J
hertz-kelvin relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.799 2374(84) x 10-11 K
hertz-kilogram relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 7.372 496 00(37) x 10-51 kg
inverse fine-structure constant Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 137.035 999 679(94)
inverse meter-atomic mass unit relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.331 025 0394(19) x 10-15 u
inverse meter-electron volt relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.239 841 875(31) x 10-6 eV
inverse meter-hartree relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.556 335 252 760(30) x 10-8 Eh
inverse meter-hertz relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 299 792 458 Hz
inverse meter-joule relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.986 445 501(99) x 10-25 J
inverse meter-kelvin relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.438 7752(25) x 10-2 K
inverse meter-kilogram relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.210 218 70(11) x 10-42 kg
inverse of conductance quantum Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 12 906.403 7787(88) Ω
joule-atomic mass unit relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.700 536 41(33) x 109 u
joule-electron volt relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.241 509 65(16) x 1018 eV
joule-hartree relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.293 712 69(11) x 1017 Eh
joule-hertz relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.509 190 450(75) x 1033 Hz
joule-inverse meter relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.034 117 47(25) x 1024 m-1
joule-kelvin relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 7.242 963(13) x 1022 K
joule-kilogram relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.112 650 056l ...  x 10-17 kg
kelvin-atomic mass unit relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 9.251 098(16) x 10-14 u
kelvin-electron volt relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 8.617 343(15) x 10-5 eV
kelvin-hartree relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.166 8153(55) x 10-6 Eh
kelvin-hertz relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.083 6644(36) x 1010 Hz
kelvin-inverse meter relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 69.503 56(12) m-1
kelvin-joule relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.380 6504(24) x 10-23 J
kelvin-kilogram relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.536 1807(27) x 10-40 kg
kilogram-atomic mass unit relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.022 141 79(30) x 1026 u
kilogram-electron volt relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.609 589 12(14) x 1035 eV
kilogram-hartree relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.061 486 16(10) x 1034 Eh
kilogram-hertz relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.356 392 733(68) x 1050 Hz
kilogram-inverse meter relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.524 439 15(23) x 1041 m-1
kilogram-joule relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 8.987 551 787l ... x 1016 J
kilogram-kelvin relationship Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.509 651(11) x 1039 K
magnetic constant ( vacuum permeability ) Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4π x 10-7
= 1.256 637 061... x 10-6
N A-2
muon Compton wavelength Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 11.734 441 04(30) x 10-15 m
muon Compton wavelength over 2 pi Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.867 594 295(47) x 10-15 m
muon-electron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 206.768 2823(52)
muon-neutron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.112 454 5167(29)
muon g factor Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -2.002 331 8414(12)
muon mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.883 531 30(11) x 10-28 kg
muon mass energy equivalent Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.692 833 510(95) x 10-11 J
muon mass energy equivalent in MeV Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 105.658 3668(38) MeV
muon mass in u Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.113 428 9256(29) u
muon molar mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.113 428 9256(29) x 10-3 kg mol-1
muon-proton magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -3.183 345 137(85)
muon-proton mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.112 609 5261(29)
muon-tau mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.945 92(97) x 10-2
natural unit of action Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.054 571 628(53) x 10-34 J s
natural unit of action in eV s Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.582 118 99(16) x 10-16 eV s
natural unit of energy Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 8.187 104 38(41) x 10-14 J
natural unit of energy in MeV Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.510 998 910(13) MeV
natural unit of length Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 386.159 264 59(53) x 10-15 m
natural unit of mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 9.109 382 15(45) x 10-31 kg
natural unit of momentum Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.730 924 06(14) x 10-22 kg m s-1
natural unit of momentum in MeV/c Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.510 998 910(13) MeV/c
natural unit of time Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.288 088 6570(18) x 10-21 s
natural unit of velocity Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 299 792 458 m s-1
neutron Compton wavelength Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.319 590 8951(20) x 10-15 m
neutron Compton wavelength over 2 pi Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.210 019 413 82(31) x 10-15 m
neutron-electron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1838.683 6605(11)
neutron g factor Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -3.826 085 45(90)
neutron mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.674 927 211(84) x 10-27 kg
neutron mass energy equivalent Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.505 349 505(75) x 10-10 J
neutron mass energy equivalent in MeV Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 939.565 346(23) MeV
neutron mass in u Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.008 664 915 97(43) u
neutron molar mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.008 664 915 97(43) x 10-3 kg mol-1
neutron-muon mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 8.892 484 09(23)
neutron-electron magnetic moment ration Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.040 668 82(25) x 10-3
neutron-proton magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -0.684 979 34(16)
neutron-proton mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.001 378 419 18(46)
neutron-tau mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.528 740(86)
Newtonian constant of gravitation Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.67428(67) x 10-11 m3 kg-1 s-2
Newtonian constant of gravitation over h-bar c Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.708 81(67) x 10-39 (GeV/c2)-2
nuclear magneton Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.050 783 24(13) x 10-27 J T-1
nuclear magneton in eV/T Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.152 451 2326(45) x 10-8 eV T-1
nuclear magneton in inverse meters per tesla Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.542 623 616(64) x 10-2 m-1 T-1
nuclear magneton in K/T Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.658 2637(64) x 10-4 K T-1
nuclear magneton in MHz/T Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 7.622 593 84(19) MHz T-1
Planck's constant Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.626 068 96(33) x 10-34 J s
Planck's constant in eV s Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.135 667 33(10) x 10-15 eV s
Planck's constant over 2 pi ( Dirac's Constant ) Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.054 571 628(53) x 10-34 J s
Planck's constant over 2 pi in eV s Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 6.582 118 99(16) x 10-16 eV s
Planck's constant over 2 pi times c in MeV fm Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 197.326 9631(49) MeV fm
Planck length Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.616 252(81) x 10-35 m
Planck mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.176 44(11) x 10-8 kg
Planck mass energy equivalent in GeV Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.220 892(61) x 1019 GeV
Planck temperature Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.416 785(71) x 1032 K
Planck time Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.391 24(27) x 10-44 s
proton charge to mass quotient Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 9.578 833 92(24) x 107 C kg-1
proton Compton wavelength Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.321 409 8446(19) x 10-15 m
proton Compton wavelength over 2 pi Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.210 308 908 61(30) x 10-15 m
proton-electron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1836.152 672 47(80)
proton g factor Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.585 694 713(46)
proton mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.672 621 637(83) x 10-27 kg
proton mass energy equivalent Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.503 277 359(75) x 10-10 J
proton mass energy equivalent in MeV Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 938.272 013(23) MeV
proton mass in u Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.007 276 466 77(10) u
proton molar mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.007 276 466 77(10) x 10-3 kg mol-1
proton-muon mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 8.880 243 39(23)
proton-neutron magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -1.459 898 06(34)
proton-neutron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.998 623 478 24(46)
proton-tau mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.528 012(86)
quantum of circulation Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.636 947 5199(50) x 10-4 m2 s-1
speed of light in vacuo ( vacuum ) Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 299 792 458 m s-1
standard acceleration of gravity earth's surface at sea level Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 9.806 65 m s-2
standard atmosphere Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 101 325 Pa
Stefan-Boltzmann constant Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.670 400(40) x 10-8 W m-2 K-4
tau Compton wavelength Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.697 72(11) x 10-15 m
tau Compton wavelength over 2 pi Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 0.111 046(18) x 10-15 m
tau-electron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3477.48(57)
tau mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.167 77(52) x 10-27 kg
tau mass energy equivalent Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.847 05(46) x 10-10 J
tau mass energy equivalent in MeV Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1776.99(29) MeV
tau mass in u Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.907 68(31) u
tau molar mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.907 68(31) x 10-3 kg mol-1
tau-muon mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 16.8183(27)
tau-neutron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.891 29(31)
tau-proton mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.893 90(31)
triton-electron magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -1.620 514 423(21) x 10-3
triton-neutron magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -1.557 185 53(37)
triton-electron mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5496.921 5269(51)
triton g factor Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.957 924 896(76)
triton mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 5.007 355 88(25) x 10-27 kg
triton mass energy equivalent Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 4.500 387 03(22) x 10-10 J
triton mass energy equivalent in MeV Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2808.920 906(70) MeV
triton mass in u Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.015 500 7134(25) u
triton molar mass Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 3.015 500 7134(25) x 10-3 kg mol-1
triton-neutron magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST -1.557 185 53(37)
triton-proton magnetic moment ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.066 639 908(10)
triton-proton mass ratio Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 2.993 717 0309(25)
unified atomic mass unit Fundamental Physical Constants from the Physical Measurement Laboratory of NIST 1.660 538 782(83) x 10-27 kg

Source: http://physics.nist.gov/cuu/Constants/index.html - Latest 2016 CODATA values

note: Values are given in Concise Form: the number in parenthesis is the standard uncertainty, multiplied by the relative standard uncertainty.