Source: https://aidb.si/d/physical-constants — CODATA recommended values of the fundamental physical constants, NIST Reference on Constants, Units, and Uncertainty (physics.nist.gov/constants).
| Quantity | Value | Standard uncertainty | Relative uncertainty | Unit | Exact | Value as published | Uncertainty as published |
|---|---|---|---|---|---|---|---|
| Angstrom star | 1.00001495e-10 | 9e-17 | 9e-7 | m | false | 1.000 014 95 e-10 | 0.000 000 90 e-10 |
| Avogadro constant | 6.02214076e+23 | 0 | 0 | mol^-1 | true | 6.022 140 76 e23 | (exact) |
| Bohr magneton | 9.2740100657e-24 | 2.9e-33 | 3.1e-10 | J T^-1 | false | 9.274 010 0657 e-24 | 0.000 000 0029 e-24 |
| Bohr magneton in Hz/T | 13996244917.1 | 4.4 | 3.1e-10 | Hz T^-1 | false | 1.399 624 491 71 e10 | 0.000 000 000 44 e10 |
| Bohr magneton in K/T | 0.67171381472 | 2.1e-10 | 3.1e-10 | K T^-1 | false | 0.671 713 814 72 | 0.000 000 000 21 |
| Bohr magneton in eV/T | 0.000057883817982 | 1.8e-14 | 3.1e-10 | eV T^-1 | false | 5.788 381 7982 e-5 | 0.000 000 0018 e-5 |
| Bohr magneton in inverse meter per tesla | 46.686447719 | 1.5e-8 | 3.2e-10 | m^-1 T^-1 | false | 46.686 447 719 | 0.000 000 015 |
| Bohr radius | 5.29177210544e-11 | 8.2e-21 | 1.5e-10 | m | false | 5.291 772 105 44 e-11 | 0.000 000 000 82 e-11 |
| Boltzmann constant | 1.380649e-23 | 0 | 0 | J K^-1 | true | 1.380 649 e-23 | (exact) |
| Boltzmann constant in Hz/K | 20836619120 | 0 | 0 | Hz K^-1 | true | 2.083 661 912... e10 | (exact) |
| Boltzmann constant in eV/K | 0.00008617333262 | 0 | 0 | eV K^-1 | true | 8.617 333 262... e-5 | (exact) |
| Boltzmann constant in inverse meter per kelvin | 69.50348004 | 0 | 0 | m^-1 K^-1 | true | 69.503 480 04... | (exact) |
| Compton wavelength | 2.42631023538e-12 | 7.6e-22 | 3.1e-10 | m | false | 2.426 310 235 38 e-12 | 0.000 000 000 76 e-12 |
| Copper x unit | 1.00207697e-13 | 2.8e-20 | 2.8e-7 | m | false | 1.002 076 97 e-13 | 0.000 000 28 e-13 |
| Faraday constant | 96485.33212 | 0 | 0 | C mol^-1 | true | 96 485.332 12... | (exact) |
| Fermi coupling constant | 0.000011663787 | 6e-12 | 5.1e-7 | GeV^-2 | false | 1.166 3787 e-5 | 0.000 0006 e-5 |
| Hartree energy | 4.359744722206e-18 | 4.8e-30 | 1.1e-12 | J | false | 4.359 744 722 2060 e-18 | 0.000 000 000 0048 e-18 |
| Hartree energy in eV | 27.211386245981 | 3e-11 | 1.1e-12 | eV | false | 27.211 386 245 981 | 0.000 000 000 030 |
| Josephson constant | 483597848400000 | 0 | 0 | Hz V^-1 | true | 483 597.848 4... e9 | (exact) |
| Loschmidt constant (273.15 K, 100 kPa) | 2.651645804e+25 | 0 | 0 | m^-3 | true | 2.651 645 804... e25 | (exact) |
| Loschmidt constant (273.15 K, 101.325 kPa) | 2.686780111e+25 | 0 | 0 | m^-3 | true | 2.686 780 111... e25 | (exact) |
| Molybdenum x unit | 1.00209952e-13 | 5.3e-20 | 5.3e-7 | m | false | 1.002 099 52 e-13 | 0.000 000 53 e-13 |
| Newtonian constant of gravitation | 6.6743e-11 | 1.5e-15 | 0.000022 | m^3 kg^-1 s^-2 | false | 6.674 30 e-11 | 0.000 15 e-11 |
| Newtonian constant of gravitation over h-bar c | 6.70883e-39 | 1.5e-43 | 0.000022 | (GeV/c^2)^-2 | false | 6.708 83 e-39 | 0.000 15 e-39 |
| Planck constant | 6.62607015e-34 | 0 | 0 | J Hz^-1 | true | 6.626 070 15 e-34 | (exact) |
| Planck constant in eV/Hz | 4.135667696e-15 | 0 | 0 | eV Hz^-1 | true | 4.135 667 696... e-15 | (exact) |
| Planck length | 1.616255e-35 | 1.8e-40 | 0.000011 | m | false | 1.616 255 e-35 | 0.000 018 e-35 |
| Planck mass | 2.176434e-8 | 2.4e-13 | 0.000011 | kg | false | 2.176 434 e-8 | 0.000 024 e-8 |
| Planck mass energy equivalent in GeV | 12208900000000000000 | 140000000000000 | 0.000011 | GeV | false | 1.220 890 e19 | 0.000 014 e19 |
| Planck temperature | 1.416784e+32 | 1.6e+27 | 0.000011 | K | false | 1.416 784 e32 | 0.000 016 e32 |
| Planck time | 5.391247e-44 | 6e-49 | 0.000011 | s | false | 5.391 247 e-44 | 0.000 060 e-44 |
| Rydberg constant | 10973731.568157 | 0.000012 | 1.1e-12 | m^-1 | false | 10 973 731.568 157 | 0.000 012 |
| Rydberg constant times c in Hz | 3289841960250000 | 3600 | 1.1e-12 | Hz | false | 3.289 841 960 2500 e15 | 0.000 000 000 0036 e15 |
| Rydberg constant times hc in J | 2.179872361103e-18 | 2.4e-30 | 1.1e-12 | J | false | 2.179 872 361 1030 e-18 | 0.000 000 000 0024 e-18 |
| Rydberg constant times hc in eV | 13.60569312299 | 1.5e-11 | 1.1e-12 | eV | false | 13.605 693 122 990 | 0.000 000 000 015 |
| Sackur-Tetrode constant (1 K, 100 kPa) | -1.15170753496 | 4.7e-10 | 4.1e-10 | false | -1.151 707 534 96 | 0.000 000 000 47 | |
| Sackur-Tetrode constant (1 K, 101.325 kPa) | -1.16487052149 | 4.7e-10 | 4e-10 | false | -1.164 870 521 49 | 0.000 000 000 47 | |
| Stefan-Boltzmann constant | 5.670374419e-8 | 0 | 0 | W m^-2 K^-4 | true | 5.670 374 419... e-8 | (exact) |
| Thomson cross section | 6.6524587051e-29 | 6.2e-38 | 9.3e-10 | m^2 | false | 6.652 458 7051 e-29 | 0.000 000 0062 e-29 |
| W to Z mass ratio | 0.88145 | 0.00013 | 0.00015 | false | 0.881 45 | 0.000 13 | |
| Wien frequency displacement law constant | 58789257570 | 0 | 0 | Hz K^-1 | true | 5.878 925 757... e10 | (exact) |
| Wien wavelength displacement law constant | 0.002897771955 | 0 | 0 | m K | true | 2.897 771 955... e-3 | (exact) |
| alpha particle mass | 6.644657345e-27 | 2.1e-36 | 3.2e-10 | kg | false | 6.644 657 3450 e-27 | 0.000 000 0021 e-27 |
| alpha particle mass energy equivalent | 5.9719201997e-10 | 1.9e-19 | 3.2e-10 | J | false | 5.971 920 1997 e-10 | 0.000 000 0019 e-10 |
| alpha particle mass energy equivalent in MeV | 3727.3794118 | 0.0000012 | 3.2e-10 | MeV | false | 3727.379 4118 | 0.000 0012 |
| alpha particle mass in u | 4.001506179129 | 6.2e-11 | 1.5e-11 | u | false | 4.001 506 179 129 | 0.000 000 000 062 |
| alpha particle molar mass | 0.0040015061833 | 1.2e-12 | 3e-10 | kg mol^-1 | false | 4.001 506 1833 e-3 | 0.000 000 0012 e-3 |
| alpha particle relative atomic mass | 4.001506179129 | 6.2e-11 | 1.5e-11 | false | 4.001 506 179 129 | 0.000 000 000 062 | |
| alpha particle rms charge radius | 1.6785e-15 | 2.1e-18 | 0.0013 | m | false | 1.6785 e-15 | 0.0021 e-15 |
| alpha particle-electron mass ratio | 7294.29954171 | 1.7e-7 | 2.3e-11 | false | 7294.299 541 71 | 0.000 000 17 | |
| alpha particle-proton mass ratio | 3.972599690252 | 7e-11 | 1.8e-11 | false | 3.972 599 690 252 | 0.000 000 000 070 | |
| atomic mass constant | 1.66053906892e-27 | 5.2e-37 | 3.1e-10 | kg | false | 1.660 539 068 92 e-27 | 0.000 000 000 52 e-27 |
| atomic mass constant energy equivalent | 1.49241808768e-10 | 4.6e-20 | 3.1e-10 | J | false | 1.492 418 087 68 e-10 | 0.000 000 000 46 e-10 |
| atomic mass constant energy equivalent in MeV | 931.49410372 | 2.9e-7 | 3.1e-10 | MeV | false | 931.494 103 72 | 0.000 000 29 |
| atomic mass unit-electron volt relationship | 931494103.72 | 0.29 | 3.1e-10 | eV | false | 9.314 941 0372 e8 | 0.000 000 0029 e8 |
| atomic mass unit-hartree relationship | 34231776.922 | 0.011 | 3.2e-10 | E_h | false | 3.423 177 6922 e7 | 0.000 000 0011 e7 |
| atomic mass unit-hertz relationship | 2.25234272185e+23 | 70000000000000 | 3.1e-10 | Hz | false | 2.252 342 721 85 e23 | 0.000 000 000 70 e23 |
| atomic mass unit-inverse meter relationship | 751300662090000 | 230000 | 3.1e-10 | m^-1 | false | 7.513 006 6209 e14 | 0.000 000 0023 e14 |
| atomic mass unit-joule relationship | 1.49241808768e-10 | 4.6e-20 | 3.1e-10 | J | false | 1.492 418 087 68 e-10 | 0.000 000 000 46 e-10 |
| atomic mass unit-kelvin relationship | 10809540206700 | 3400 | 3.1e-10 | K | false | 1.080 954 020 67 e13 | 0.000 000 000 34 e13 |
| atomic mass unit-kilogram relationship | 1.66053906892e-27 | 5.2e-37 | 3.1e-10 | kg | false | 1.660 539 068 92 e-27 | 0.000 000 000 52 e-27 |
| atomic unit of 1st hyperpolarizability | 3.2063612996e-53 | 1.5e-62 | 4.7e-10 | C^3 m^3 J^-2 | false | 3.206 361 2996 e-53 | 0.000 000 0015 e-53 |
| atomic unit of 2nd hyperpolarizability | 6.2353799735e-65 | 3.9e-74 | 6.3e-10 | C^4 m^4 J^-3 | false | 6.235 379 9735 e-65 | 0.000 000 0039 e-65 |
| atomic unit of action | 1.054571817e-34 | 0 | 0 | J s | true | 1.054 571 817... e-34 | (exact) |
| atomic unit of charge | 1.602176634e-19 | 0 | 0 | C | true | 1.602 176 634 e-19 | (exact) |
| atomic unit of charge density | 1081202386770 | 510 | 4.7e-10 | C m^-3 | false | 1.081 202 386 77 e12 | 0.000 000 000 51 e12 |
| atomic unit of current | 0.0066236182375082 | 7.2e-15 | 1.1e-12 | A | false | 6.623 618 237 5082 e-3 | 0.000 000 000 0072 e-3 |
| atomic unit of electric dipole mom. | 8.4783536198e-30 | 1.3e-39 | 1.5e-10 | C m | false | 8.478 353 6198 e-30 | 0.000 000 0013 e-30 |
| atomic unit of electric field | 514220675112 | 80 | 1.6e-10 | V m^-1 | false | 5.142 206 751 12 e11 | 0.000 000 000 80 e11 |
| atomic unit of electric field gradient | 9.7173624424e+21 | 3000000000000 | 3.1e-10 | V m^-2 | false | 9.717 362 4424 e21 | 0.000 000 0030 e21 |
| atomic unit of electric polarizability | 1.64877727212e-41 | 5.1e-51 | 3.1e-10 | C^2 m^2 J^-1 | false | 1.648 777 272 12 e-41 | 0.000 000 000 51 e-41 |
| atomic unit of electric potential | 27.211386245981 | 3e-11 | 1.1e-12 | V | false | 27.211 386 245 981 | 0.000 000 000 030 |
| atomic unit of electric quadrupole mom. | 4.4865515185e-40 | 1.4e-49 | 3.1e-10 | C m^2 | false | 4.486 551 5185 e-40 | 0.000 000 0014 e-40 |
| atomic unit of energy | 4.359744722206e-18 | 4.8e-30 | 1.1e-12 | J | false | 4.359 744 722 2060 e-18 | 0.000 000 000 0048 e-18 |
| atomic unit of force | 8.2387235038e-8 | 1.3e-17 | 1.6e-10 | N | false | 8.238 723 5038 e-8 | 0.000 000 0013 e-8 |
| atomic unit of length | 5.29177210544e-11 | 8.2e-21 | 1.5e-10 | m | false | 5.291 772 105 44 e-11 | 0.000 000 000 82 e-11 |
| atomic unit of mag. dipole mom. | 1.85480201315e-23 | 5.8e-33 | 3.1e-10 | J T^-1 | false | 1.854 802 013 15 e-23 | 0.000 000 000 58 e-23 |
| atomic unit of mag. flux density | 235051.757077 | 0.000073 | 3.1e-10 | T | false | 2.350 517 570 77 e5 | 0.000 000 000 73 e5 |
| atomic unit of magnetizability | 7.8910365794e-29 | 4.9e-38 | 6.2e-10 | J T^-2 | false | 7.891 036 5794 e-29 | 0.000 000 0049 e-29 |
| atomic unit of mass | 9.1093837139e-31 | 2.8e-40 | 3.1e-10 | kg | false | 9.109 383 7139 e-31 | 0.000 000 0028 e-31 |
| atomic unit of momentum | 1.99285191545e-24 | 3.1e-34 | 1.6e-10 | kg m s^-1 | false | 1.992 851 915 45 e-24 | 0.000 000 000 31 e-24 |
| atomic unit of permittivity | 1.1126500562e-10 | 1.7e-20 | 1.5e-10 | F m^-1 | false | 1.112 650 056 20 e-10 | 0.000 000 000 17 e-10 |
| atomic unit of time | 2.4188843265864e-17 | 2.6e-29 | 1.1e-12 | s | false | 2.418 884 326 5864 e-17 | 0.000 000 000 0026 e-17 |
| atomic unit of velocity | 2187691.26216 | 0.00034 | 1.6e-10 | m s^-1 | false | 2.187 691 262 16 e6 | 0.000 000 000 34 e6 |
| characteristic impedance of vacuum | 376.730313412 | 5.9e-8 | 1.6e-10 | ohm | false | 376.730 313 412 | 0.000 000 059 |
| classical electron radius | 2.8179403205e-15 | 1.3e-24 | 4.6e-10 | m | false | 2.817 940 3205 e-15 | 0.000 000 0013 e-15 |
| conductance quantum | 0.00007748091729 | 0 | 0 | S | true | 7.748 091 729... e-5 | (exact) |
| conventional value of Josephson constant | 483597900000000 | 0 | 0 | Hz V^-1 | true | 483 597.9 e9 | (exact) |
| conventional value of ampere-90 | 1.00000008887 | 0 | 0 | A | true | 1.000 000 088 87... | (exact) |
| conventional value of coulomb-90 | 1.00000008887 | 0 | 0 | C | true | 1.000 000 088 87... | (exact) |
| conventional value of farad-90 | 0.9999999822 | 0 | 0 | F | true | 0.999 999 982 20... | (exact) |
| conventional value of henry-90 | 1.00000001779 | 0 | 0 | H | true | 1.000 000 017 79... | (exact) |
| conventional value of ohm-90 | 1.00000001779 | 0 | 0 | ohm | true | 1.000 000 017 79... | (exact) |
| conventional value of volt-90 | 1.00000010666 | 0 | 0 | V | true | 1.000 000 106 66... | (exact) |
| conventional value of von Klitzing constant | 25812.807 | 0 | 0 | ohm | true | 25 812.807 | (exact) |
| conventional value of watt-90 | 1.00000019553 | 0 | 0 | W | true | 1.000 000 195 53... | (exact) |
| deuteron g factor | 0.8574382335 | 2.2e-9 | 2.6e-9 | false | 0.857 438 2335 | 0.000 000 0022 | |
| deuteron mag. mom. | 4.330735087e-27 | 1.1e-35 | 2.5e-9 | J T^-1 | false | 4.330 735 087 e-27 | 0.000 000 011 e-27 |
| deuteron mag. mom. to Bohr magneton ratio | 0.0004669754568 | 1.2e-12 | 2.6e-9 | false | 4.669 754 568 e-4 | 0.000 000 012 e-4 | |
| deuteron mag. mom. to nuclear magneton ratio | 0.8574382335 | 2.2e-9 | 2.6e-9 | false | 0.857 438 2335 | 0.000 000 0022 | |
| deuteron mass | 3.3435837768e-27 | 1e-36 | 3e-10 | kg | false | 3.343 583 7768 e-27 | 0.000 000 0010 e-27 |
| deuteron mass energy equivalent | 3.00506323491e-10 | 9.4e-20 | 3.1e-10 | J | false | 3.005 063 234 91 e-10 | 0.000 000 000 94 e-10 |
| deuteron mass energy equivalent in MeV | 1875.612945 | 5.8e-7 | 3.1e-10 | MeV | false | 1875.612 945 00 | 0.000 000 58 |
| deuteron mass in u | 2.013553212544 | 1.5e-11 | 7.4e-12 | u | false | 2.013 553 212 544 | 0.000 000 000 015 |
| deuteron molar mass | 0.00201355321466 | 6.3e-13 | 3.1e-10 | kg mol^-1 | false | 2.013 553 214 66 e-3 | 0.000 000 000 63 e-3 |
| deuteron relative atomic mass | 2.013553212544 | 1.5e-11 | 7.4e-12 | false | 2.013 553 212 544 | 0.000 000 000 015 | |
| deuteron rms charge radius | 2.12778e-15 | 2.7e-19 | 0.00013 | m | false | 2.127 78 e-15 | 0.000 27 e-15 |
| deuteron-electron mag. mom. ratio | -0.000466434555 | 1.2e-12 | 2.6e-9 | false | -4.664 345 550 e-4 | 0.000 000 012 e-4 | |
| deuteron-electron mass ratio | 3670.482967655 | 6.3e-8 | 1.7e-11 | false | 3670.482 967 655 | 0.000 000 063 | |
| deuteron-neutron mag. mom. ratio | -0.44820652 | 1.1e-7 | 2.5e-7 | false | -0.448 206 52 | 0.000 000 11 | |
| deuteron-proton mag. mom. ratio | 0.3070122093 | 7.9e-10 | 2.6e-9 | false | 0.307 012 209 30 | 0.000 000 000 79 | |
| deuteron-proton mass ratio | 1.9990075012699 | 8.4e-12 | 4.2e-12 | false | 1.999 007 501 2699 | 0.000 000 000 0084 | |
| electron charge to mass quotient | -175882000838 | 55 | 3.1e-10 | C kg^-1 | false | -1.758 820 008 38 e11 | 0.000 000 000 55 e11 |
| electron g factor | -2.00231930436092 | 3.6e-13 | 1.8e-13 | false | -2.002 319 304 360 92 | 0.000 000 000 000 36 | |
| electron gyromag. ratio | 176085962784 | 55 | 3.1e-10 | s^-1 T^-1 | false | 1.760 859 627 84 e11 | 0.000 000 000 55 e11 |
| electron gyromag. ratio in MHz/T | 28024.9513861 | 0.0000087 | 3.1e-10 | MHz T^-1 | false | 28 024.951 3861 | 0.000 0087 |
| electron mag. mom. | -9.2847646917e-24 | 2.9e-33 | 3.1e-10 | J T^-1 | false | -9.284 764 6917 e-24 | 0.000 000 0029 e-24 |
| electron mag. mom. anomaly | 0.00115965218046 | 1.8e-13 | 1.6e-10 | false | 1.159 652 180 46 e-3 | 0.000 000 000 18 e-3 | |
| electron mag. mom. to Bohr magneton ratio | -1.00115965218046 | 1.8e-13 | 1.8e-13 | false | -1.001 159 652 180 46 | 0.000 000 000 000 18 | |
| electron mag. mom. to nuclear magneton ratio | -1838.281971877 | 3.2e-8 | 1.7e-11 | false | -1838.281 971 877 | 0.000 000 032 | |
| electron mass | 9.1093837139e-31 | 2.8e-40 | 3.1e-10 | kg | false | 9.109 383 7139 e-31 | 0.000 000 0028 e-31 |
| electron mass energy equivalent | 8.187105788e-14 | 2.6e-23 | 3.2e-10 | J | false | 8.187 105 7880 e-14 | 0.000 000 0026 e-14 |
| electron mass energy equivalent in MeV | 0.51099895069 | 1.6e-10 | 3.1e-10 | MeV | false | 0.510 998 950 69 | 0.000 000 000 16 |
| electron mass in u | 0.0005485799090441 | 9.7e-15 | 1.8e-11 | u | false | 5.485 799 090 441 e-4 | 0.000 000 000 097 e-4 |
| electron molar mass | 5.4857990962e-7 | 1.7e-16 | 3.1e-10 | kg mol^-1 | false | 5.485 799 0962 e-7 | 0.000 000 0017 e-7 |
| electron relative atomic mass | 0.0005485799090441 | 9.7e-15 | 1.8e-11 | false | 5.485 799 090 441 e-4 | 0.000 000 000 097 e-4 | |
| electron to alpha particle mass ratio | 0.0001370933554733 | 3.2e-15 | 2.3e-11 | false | 1.370 933 554 733 e-4 | 0.000 000 000 032 e-4 | |
| electron to shielded helion mag. mom. ratio | 864.05823986 | 7e-7 | 8.1e-10 | false | 864.058 239 86 | 0.000 000 70 | |
| electron to shielded proton mag. mom. ratio | -658.2275856 | 0.0000027 | 4.1e-9 | false | -658.227 5856 | 0.000 0027 | |
| electron volt | 1.602176634e-19 | 0 | 0 | J | true | 1.602 176 634 e-19 | (exact) |
| electron volt-atomic mass unit relationship | 1.07354410083e-9 | 3.3e-19 | 3.1e-10 | u | false | 1.073 544 100 83 e-9 | 0.000 000 000 33 e-9 |
| electron volt-hartree relationship | 0.036749322175665 | 4e-14 | 1.1e-12 | E_h | false | 3.674 932 217 5665 e-2 | 0.000 000 000 0040 e-2 |
| electron volt-hertz relationship | 241798924200000 | 0 | 0 | Hz | true | 2.417 989 242... e14 | (exact) |
| electron volt-inverse meter relationship | 806554.3937 | 0 | 0 | m^-1 | true | 8.065 543 937... e5 | (exact) |
| electron volt-joule relationship | 1.602176634e-19 | 0 | 0 | J | true | 1.602 176 634 e-19 | (exact) |
| electron volt-kelvin relationship | 11604.51812 | 0 | 0 | K | true | 1.160 451 812... e4 | (exact) |
| electron volt-kilogram relationship | 1.782661921e-36 | 0 | 0 | kg | true | 1.782 661 921... e-36 | (exact) |
| electron-deuteron mag. mom. ratio | -2143.9234921 | 0.0000056 | 2.6e-9 | false | -2143.923 4921 | 0.000 0056 | |
| electron-deuteron mass ratio | 0.0002724437107629 | 4.7e-15 | 1.7e-11 | false | 2.724 437 107 629 e-4 | 0.000 000 000 047 e-4 | |
| electron-helion mass ratio | 0.0001819543074649 | 5.3e-15 | 2.9e-11 | false | 1.819 543 074 649 e-4 | 0.000 000 000 053 e-4 | |
| electron-muon mag. mom. ratio | 206.7669881 | 0.0000046 | 2.2e-8 | false | 206.766 9881 | 0.000 0046 | |
| electron-muon mass ratio | 0.0048363317 | 1.1e-10 | 2.3e-8 | false | 4.836 331 70 e-3 | 0.000 000 11 e-3 | |
| electron-neutron mag. mom. ratio | 960.92048 | 0.00023 | 2.4e-7 | false | 960.920 48 | 0.000 23 | |
| electron-neutron mass ratio | 0.00054386734416 | 2.2e-13 | 4e-10 | false | 5.438 673 4416 e-4 | 0.000 000 0022 e-4 | |
| electron-proton mag. mom. ratio | -658.21068789 | 1.9e-7 | 2.9e-10 | false | -658.210 687 89 | 0.000 000 19 | |
| electron-proton mass ratio | 0.0005446170214889 | 9.4e-15 | 1.7e-11 | false | 5.446 170 214 889 e-4 | 0.000 000 000 094 e-4 | |
| electron-tau mass ratio | 0.000287585 | 1.9e-8 | 0.000066 | false | 2.875 85 e-4 | 0.000 19 e-4 | |
| electron-triton mass ratio | 0.0001819200062327 | 6.8e-15 | 3.7e-11 | false | 1.819 200 062 327 e-4 | 0.000 000 000 068 e-4 | |
| elementary charge | 1.602176634e-19 | 0 | 0 | C | true | 1.602 176 634 e-19 | (exact) |
| elementary charge over h-bar | 1519267447000000 | 0 | 0 | A J^-1 | true | 1.519 267 447... e15 | (exact) |
| fine-structure constant | 0.0072973525643 | 1.1e-12 | 1.5e-10 | false | 7.297 352 5643 e-3 | 0.000 000 0011 e-3 | |
| first radiation constant | 3.741771852e-16 | 0 | 0 | W m^2 | true | 3.741 771 852... e-16 | (exact) |
| first radiation constant for spectral radiance | 1.191042972e-16 | 0 | 0 | W m^2 sr^-1 | true | 1.191 042 972... e-16 | (exact) |
| hartree-atomic mass unit relationship | 2.92126231797e-8 | 9.1e-18 | 3.1e-10 | u | false | 2.921 262 317 97 e-8 | 0.000 000 000 91 e-8 |
| hartree-electron volt relationship | 27.211386245981 | 3e-11 | 1.1e-12 | eV | false | 27.211 386 245 981 | 0.000 000 000 030 |
| hartree-hertz relationship | 6579683920499900 | 7200 | 1.1e-12 | Hz | false | 6.579 683 920 4999 e15 | 0.000 000 000 0072 e15 |
| hartree-inverse meter relationship | 21947463.136314 | 0.000024 | 1.1e-12 | m^-1 | false | 2.194 746 313 6314 e7 | 0.000 000 000 0024 e7 |
| hartree-joule relationship | 4.359744722206e-18 | 4.8e-30 | 1.1e-12 | J | false | 4.359 744 722 2060 e-18 | 0.000 000 000 0048 e-18 |
| hartree-kelvin relationship | 315775.02480398 | 3.4e-7 | 1.1e-12 | K | false | 3.157 750 248 0398 e5 | 0.000 000 000 0034 e5 |
| hartree-kilogram relationship | 4.8508702095419e-35 | 5.3e-47 | 1.1e-12 | kg | false | 4.850 870 209 5419 e-35 | 0.000 000 000 0053 e-35 |
| helion g factor | -4.2552506995 | 3.4e-9 | 8e-10 | false | -4.255 250 6995 | 0.000 000 0034 | |
| helion mag. mom. | -1.07461755198e-26 | 9.3e-36 | 8.7e-10 | J T^-1 | false | -1.074 617 551 98 e-26 | 0.000 000 000 93 e-26 |
| helion mag. mom. to Bohr magneton ratio | -0.00115874098083 | 9.4e-13 | 8.1e-10 | false | -1.158 740 980 83 e-3 | 0.000 000 000 94 e-3 | |
| helion mag. mom. to nuclear magneton ratio | -2.1276253498 | 1.7e-9 | 8e-10 | false | -2.127 625 3498 | 0.000 000 0017 | |
| helion mass | 5.0064127862e-27 | 1.6e-36 | 3.2e-10 | kg | false | 5.006 412 7862 e-27 | 0.000 000 0016 e-27 |
| helion mass energy equivalent | 4.4995394185e-10 | 1.4e-19 | 3.1e-10 | J | false | 4.499 539 4185 e-10 | 0.000 000 0014 e-10 |
| helion mass energy equivalent in MeV | 2808.39161112 | 8.8e-7 | 3.1e-10 | MeV | false | 2808.391 611 12 | 0.000 000 88 |
| helion mass in u | 3.014932246932 | 7.4e-11 | 2.5e-11 | u | false | 3.014 932 246 932 | 0.000 000 000 074 |
| helion molar mass | 0.0030149322501 | 9.4e-13 | 3.1e-10 | kg mol^-1 | false | 3.014 932 250 10 e-3 | 0.000 000 000 94 e-3 |
| helion relative atomic mass | 3.014932246932 | 7.4e-11 | 2.5e-11 | false | 3.014 932 246 932 | 0.000 000 000 074 | |
| helion shielding shift | 0.000059967029 | 2.3e-11 | 3.8e-7 | false | 5.996 7029 e-5 | 0.000 0023 e-5 | |
| helion-electron mass ratio | 5495.88527984 | 1.6e-7 | 2.9e-11 | false | 5495.885 279 84 | 0.000 000 16 | |
| helion-proton mass ratio | 2.993152671552 | 7e-11 | 2.3e-11 | false | 2.993 152 671 552 | 0.000 000 000 070 | |
| hertz-atomic mass unit relationship | 4.439821659e-24 | 1.4e-33 | 3.2e-10 | u | false | 4.439 821 6590 e-24 | 0.000 000 0014 e-24 |
| hertz-electron volt relationship | 4.135667696e-15 | 0 | 0 | eV | true | 4.135 667 696... e-15 | (exact) |
| hertz-hartree relationship | 1.5198298460574e-16 | 1.7e-28 | 1.1e-12 | E_h | false | 1.519 829 846 0574 e-16 | 0.000 000 000 0017 e-16 |
| hertz-inverse meter relationship | 3.335640951e-9 | 0 | 0 | m^-1 | true | 3.335 640 951... e-9 | (exact) |
| hertz-joule relationship | 6.62607015e-34 | 0 | 0 | J | true | 6.626 070 15 e-34 | (exact) |
| hertz-kelvin relationship | 4.799243073e-11 | 0 | 0 | K | true | 4.799 243 073... e-11 | (exact) |
| hertz-kilogram relationship | 7.372497323e-51 | 0 | 0 | kg | true | 7.372 497 323... e-51 | (exact) |
| hyperfine transition frequency of Cs-133 | 9192631770 | 0 | 0 | Hz | true | 9 192 631 770 | (exact) |
| inverse fine-structure constant | 137.035999177 | 2.1e-8 | 1.5e-10 | false | 137.035 999 177 | 0.000 000 021 | |
| inverse meter-atomic mass unit relationship | 1.33102504824e-15 | 4.1e-25 | 3.1e-10 | u | false | 1.331 025 048 24 e-15 | 0.000 000 000 41 e-15 |
| inverse meter-electron volt relationship | 0.000001239841984 | 0 | 0 | eV | true | 1.239 841 984... e-6 | (exact) |
| inverse meter-hartree relationship | 4.5563352529132e-8 | 5e-20 | 1.1e-12 | E_h | false | 4.556 335 252 9132 e-8 | 0.000 000 000 0050 e-8 |
| inverse meter-hertz relationship | 299792458 | 0 | 0 | Hz | true | 299 792 458 | (exact) |
| inverse meter-joule relationship | 1.986445857e-25 | 0 | 0 | J | true | 1.986 445 857... e-25 | (exact) |
| inverse meter-kelvin relationship | 0.01438776877 | 0 | 0 | K | true | 1.438 776 877... e-2 | (exact) |
| inverse meter-kilogram relationship | 2.210219094e-42 | 0 | 0 | kg | true | 2.210 219 094... e-42 | (exact) |
| inverse of conductance quantum | 12906.40372 | 0 | 0 | ohm | true | 12 906.403 72... | (exact) |
| joule-atomic mass unit relationship | 6700535247.1 | 2.1 | 3.1e-10 | u | false | 6.700 535 2471 e9 | 0.000 000 0021 e9 |
| joule-electron volt relationship | 6241509074000000000 | 0 | 0 | eV | true | 6.241 509 074... e18 | (exact) |
| joule-hartree relationship | 229371227839690000 | 250000 | 1.1e-12 | E_h | false | 2.293 712 278 3969 e17 | 0.000 000 000 0025 e17 |
| joule-hertz relationship | 1.509190179e+33 | 0 | 0 | Hz | true | 1.509 190 179... e33 | (exact) |
| joule-inverse meter relationship | 5.034116567e+24 | 0 | 0 | m^-1 | true | 5.034 116 567... e24 | (exact) |
| joule-kelvin relationship | 7.242970516e+22 | 0 | 0 | K | true | 7.242 970 516... e22 | (exact) |
| joule-kilogram relationship | 1.112650056e-17 | 0 | 0 | kg | true | 1.112 650 056... e-17 | (exact) |
| kelvin-atomic mass unit relationship | 9.2510872884e-14 | 2.9e-23 | 3.1e-10 | u | false | 9.251 087 2884 e-14 | 0.000 000 0029 e-14 |
| kelvin-electron volt relationship | 0.00008617333262 | 0 | 0 | eV | true | 8.617 333 262... e-5 | (exact) |
| kelvin-hartree relationship | 0.0000031668115634564 | 3.5e-18 | 1.1e-12 | E_h | false | 3.166 811 563 4564 e-6 | 0.000 000 000 0035 e-6 |
| kelvin-hertz relationship | 20836619120 | 0 | 0 | Hz | true | 2.083 661 912... e10 | (exact) |
| kelvin-inverse meter relationship | 69.50348004 | 0 | 0 | m^-1 | true | 69.503 480 04... | (exact) |
| kelvin-joule relationship | 1.380649e-23 | 0 | 0 | J | true | 1.380 649 e-23 | (exact) |
| kelvin-kilogram relationship | 1.536179187e-40 | 0 | 0 | kg | true | 1.536 179 187... e-40 | (exact) |
| kilogram-atomic mass unit relationship | 6.0221407537e+26 | 190000000000000000 | 3.2e-10 | u | false | 6.022 140 7537 e26 | 0.000 000 0019 e26 |
| kilogram-electron volt relationship | 5.609588603e+35 | 0 | 0 | eV | true | 5.609 588 603... e35 | (exact) |
| kilogram-hartree relationship | 2.0614857887415e+34 | 2.2e+22 | 1.1e-12 | E_h | false | 2.061 485 788 7415 e34 | 0.000 000 000 0022 e34 |
| kilogram-hertz relationship | 1.356392489e+50 | 0 | 0 | Hz | true | 1.356 392 489... e50 | (exact) |
| kilogram-inverse meter relationship | 4.524438335e+41 | 0 | 0 | m^-1 | true | 4.524 438 335... e41 | (exact) |
| kilogram-joule relationship | 89875517870000000 | 0 | 0 | J | true | 8.987 551 787... e16 | (exact) |
| kilogram-kelvin relationship | 6.50965726e+39 | 0 | 0 | K | true | 6.509 657 260... e39 | (exact) |
| lattice parameter of silicon | 5.431020511e-10 | 8.9e-18 | 1.6e-8 | m | false | 5.431 020 511 e-10 | 0.000 000 089 e-10 |
| lattice spacing of ideal Si (220) | 1.920155716e-10 | 3.2e-18 | 1.7e-8 | m | false | 1.920 155 716 e-10 | 0.000 000 032 e-10 |
| luminous efficacy | 683 | 0 | 0 | lm W^-1 | true | 683 | (exact) |
| mag. flux quantum | 2.067833848e-15 | 0 | 0 | Wb | true | 2.067 833 848... e-15 | (exact) |
| molar Planck constant | 3.990312712e-10 | 0 | 0 | J Hz^-1 mol^-1 | true | 3.990 312 712... e-10 | (exact) |
| molar gas constant | 8.314462618 | 0 | 0 | J mol^-1 K^-1 | true | 8.314 462 618... | (exact) |
| molar mass constant | 0.00100000000105 | 3.1e-13 | 3.1e-10 | kg mol^-1 | false | 1.000 000 001 05 e-3 | 0.000 000 000 31 e-3 |
| molar mass of carbon-12 | 0.0120000000126 | 3.7e-12 | 3.1e-10 | kg mol^-1 | false | 12.000 000 0126 e-3 | 0.000 000 0037 e-3 |
| molar volume of ideal gas (273.15 K, 100 kPa) | 0.02271095464 | 0 | 0 | m^3 mol^-1 | true | 22.710 954 64... e-3 | (exact) |
| molar volume of ideal gas (273.15 K, 101.325 kPa) | 0.02241396954 | 0 | 0 | m^3 mol^-1 | true | 22.413 969 54... e-3 | (exact) |
| molar volume of silicon | 0.00001205883199 | 6e-13 | 5e-8 | m^3 mol^-1 | false | 1.205 883 199 e-5 | 0.000 000 060 e-5 |
| muon Compton wavelength | 1.17344411e-14 | 2.6e-22 | 2.2e-8 | m | false | 1.173 444 110 e-14 | 0.000 000 026 e-14 |
| muon g factor | -2.00233184123 | 8.2e-10 | 4.1e-10 | false | -2.002 331 841 23 | 0.000 000 000 82 | |
| muon mag. mom. | -4.4904483e-26 | 1e-33 | 2.2e-8 | J T^-1 | false | -4.490 448 30 e-26 | 0.000 000 10 e-26 |
| muon mag. mom. anomaly | 0.00116592062 | 4.1e-10 | 3.5e-7 | false | 1.165 920 62 e-3 | 0.000 000 41 e-3 | |
| muon mag. mom. to Bohr magneton ratio | -0.00484197048 | 1.1e-10 | 2.3e-8 | false | -4.841 970 48 e-3 | 0.000 000 11 e-3 | |
| muon mag. mom. to nuclear magneton ratio | -8.89059704 | 2e-7 | 2.2e-8 | false | -8.890 597 04 | 0.000 000 20 | |
| muon mass | 1.883531627e-28 | 4.2e-36 | 2.2e-8 | kg | false | 1.883 531 627 e-28 | 0.000 000 042 e-28 |
| muon mass energy equivalent | 1.692833804e-11 | 3.8e-19 | 2.2e-8 | J | false | 1.692 833 804 e-11 | 0.000 000 038 e-11 |
| muon mass energy equivalent in MeV | 105.6583755 | 0.0000023 | 2.2e-8 | MeV | false | 105.658 3755 | 0.000 0023 |
| muon mass in u | 0.1134289257 | 2.5e-9 | 2.2e-8 | u | false | 0.113 428 9257 | 0.000 000 0025 |
| muon molar mass | 0.0001134289258 | 2.5e-12 | 2.2e-8 | kg mol^-1 | false | 1.134 289 258 e-4 | 0.000 000 025 e-4 |
| muon-electron mass ratio | 206.7682827 | 0.0000046 | 2.2e-8 | false | 206.768 2827 | 0.000 0046 | |
| muon-neutron mass ratio | 0.1124545168 | 2.5e-9 | 2.2e-8 | false | 0.112 454 5168 | 0.000 000 0025 | |
| muon-proton mag. mom. ratio | -3.183345146 | 7.1e-8 | 2.2e-8 | false | -3.183 345 146 | 0.000 000 071 | |
| muon-proton mass ratio | 0.1126095262 | 2.5e-9 | 2.2e-8 | false | 0.112 609 5262 | 0.000 000 0025 | |
| muon-tau mass ratio | 0.0594635 | 0.000004 | 0.000067 | false | 5.946 35 e-2 | 0.000 40 e-2 | |
| natural unit of action | 1.054571817e-34 | 0 | 0 | J s | true | 1.054 571 817... e-34 | (exact) |
| natural unit of action in eV s | 6.582119569e-16 | 0 | 0 | eV s | true | 6.582 119 569... e-16 | (exact) |
| natural unit of energy | 8.187105788e-14 | 2.6e-23 | 3.2e-10 | J | false | 8.187 105 7880 e-14 | 0.000 000 0026 e-14 |
| natural unit of energy in MeV | 0.51099895069 | 1.6e-10 | 3.1e-10 | MeV | false | 0.510 998 950 69 | 0.000 000 000 16 |
| natural unit of length | 3.8615926744e-13 | 1.2e-22 | 3.1e-10 | m | false | 3.861 592 6744 e-13 | 0.000 000 0012 e-13 |
| natural unit of mass | 9.1093837139e-31 | 2.8e-40 | 3.1e-10 | kg | false | 9.109 383 7139 e-31 | 0.000 000 0028 e-31 |
| natural unit of momentum | 2.73092453446e-22 | 8.5e-32 | 3.1e-10 | kg m s^-1 | false | 2.730 924 534 46 e-22 | 0.000 000 000 85 e-22 |
| natural unit of momentum in MeV/c | 0.51099895069 | 1.6e-10 | 3.1e-10 | MeV/c | false | 0.510 998 950 69 | 0.000 000 000 16 |
| natural unit of time | 1.28808866644e-21 | 4e-31 | 3.1e-10 | s | false | 1.288 088 666 44 e-21 | 0.000 000 000 40 e-21 |
| natural unit of velocity | 299792458 | 0 | 0 | m s^-1 | true | 299 792 458 | (exact) |
| neutron Compton wavelength | 1.31959090382e-15 | 6.7e-25 | 5.1e-10 | m | false | 1.319 590 903 82 e-15 | 0.000 000 000 67 e-15 |
| neutron g factor | -3.82608552 | 9e-7 | 2.4e-7 | false | -3.826 085 52 | 0.000 000 90 | |
| neutron gyromag. ratio | 183247174 | 43 | 2.3e-7 | s^-1 T^-1 | false | 1.832 471 74 e8 | 0.000 000 43 e8 |
| neutron gyromag. ratio in MHz/T | 29.1646935 | 0.0000069 | 2.4e-7 | MHz T^-1 | false | 29.164 6935 | 0.000 0069 |
| neutron mag. mom. | -9.6623653e-27 | 2.3e-33 | 2.4e-7 | J T^-1 | false | -9.662 3653 e-27 | 0.000 0023 e-27 |
| neutron mag. mom. to Bohr magneton ratio | -0.00104187565 | 2.5e-10 | 2.4e-7 | false | -1.041 875 65 e-3 | 0.000 000 25 e-3 | |
| neutron mag. mom. to nuclear magneton ratio | -1.91304276 | 4.5e-7 | 2.4e-7 | false | -1.913 042 76 | 0.000 000 45 | |
| neutron mass | 1.67492750056e-27 | 8.5e-37 | 5.1e-10 | kg | false | 1.674 927 500 56 e-27 | 0.000 000 000 85 e-27 |
| neutron mass energy equivalent | 1.50534976514e-10 | 7.6e-20 | 5e-10 | J | false | 1.505 349 765 14 e-10 | 0.000 000 000 76 e-10 |
| neutron mass energy equivalent in MeV | 939.56542194 | 4.8e-7 | 5.1e-10 | MeV | false | 939.565 421 94 | 0.000 000 48 |
| neutron mass in u | 1.00866491606 | 4e-10 | 4e-10 | u | false | 1.008 664 916 06 | 0.000 000 000 40 |
| neutron molar mass | 0.00100866491712 | 5.1e-13 | 5.1e-10 | kg mol^-1 | false | 1.008 664 917 12 e-3 | 0.000 000 000 51 e-3 |
| neutron relative atomic mass | 1.00866491606 | 4e-10 | 4e-10 | false | 1.008 664 916 06 | 0.000 000 000 40 | |
| neutron to shielded proton mag. mom. ratio | -0.68499694 | 1.6e-7 | 2.3e-7 | false | -0.684 996 94 | 0.000 000 16 | |
| neutron-electron mag. mom. ratio | 0.00104066884 | 2.4e-10 | 2.3e-7 | false | 1.040 668 84 e-3 | 0.000 000 24 e-3 | |
| neutron-electron mass ratio | 1838.683662 | 7.4e-7 | 4e-10 | false | 1838.683 662 00 | 0.000 000 74 | |
| neutron-muon mass ratio | 8.89248408 | 2e-7 | 2.2e-8 | false | 8.892 484 08 | 0.000 000 20 | |
| neutron-proton mag. mom. ratio | -0.68497935 | 1.6e-7 | 2.3e-7 | false | -0.684 979 35 | 0.000 000 16 | |
| neutron-proton mass difference | 2.30557461e-30 | 6.7e-37 | 2.9e-7 | kg | false | 2.305 574 61 e-30 | 0.000 000 67 e-30 |
| neutron-proton mass difference energy equivalent | 2.07214712e-13 | 6e-20 | 2.9e-7 | J | false | 2.072 147 12 e-13 | 0.000 000 60 e-13 |
| neutron-proton mass difference energy equivalent in MeV | 1.29333251 | 3.8e-7 | 2.9e-7 | MeV | false | 1.293 332 51 | 0.000 000 38 |
| neutron-proton mass difference in u | 0.00138844948 | 4e-10 | 2.9e-7 | u | false | 1.388 449 48 e-3 | 0.000 000 40 e-3 |
| neutron-proton mass ratio | 1.00137841946 | 4e-10 | 4e-10 | false | 1.001 378 419 46 | 0.000 000 000 40 | |
| neutron-tau mass ratio | 0.528779 | 0.000036 | 0.000068 | false | 0.528 779 | 0.000 036 | |
| nuclear magneton | 5.0507837393e-27 | 1.6e-36 | 3.2e-10 | J T^-1 | false | 5.050 783 7393 e-27 | 0.000 000 0016 e-27 |
| nuclear magneton in K/T | 0.00036582677706 | 1.1e-13 | 3e-10 | K T^-1 | false | 3.658 267 7706 e-4 | 0.000 000 0011 e-4 |
| nuclear magneton in MHz/T | 7.6225932188 | 2.4e-9 | 3.1e-10 | MHz T^-1 | false | 7.622 593 2188 | 0.000 000 0024 |
| nuclear magneton in eV/T | 3.15245125417e-8 | 9.8e-18 | 3.1e-10 | eV T^-1 | false | 3.152 451 254 17 e-8 | 0.000 000 000 98 e-8 |
| nuclear magneton in inverse meter per tesla | 0.0254262341009 | 7.9e-12 | 3.1e-10 | m^-1 T^-1 | false | 2.542 623 410 09 e-2 | 0.000 000 000 79 e-2 |
| proton Compton wavelength | 1.3214098536e-15 | 4.1e-25 | 3.1e-10 | m | false | 1.321 409 853 60 e-15 | 0.000 000 000 41 e-15 |
| proton charge to mass quotient | 95788331.43 | 0.03 | 3.1e-10 | C kg^-1 | false | 9.578 833 1430 e7 | 0.000 000 0030 e7 |
| proton g factor | 5.5856946893 | 1.6e-9 | 2.9e-10 | false | 5.585 694 6893 | 0.000 000 0016 | |
| proton gyromag. ratio | 267522187.08 | 0.11 | 4.1e-10 | s^-1 T^-1 | false | 2.675 221 8708 e8 | 0.000 000 0011 e8 |
| proton gyromag. ratio in MHz/T | 42.577478461 | 1.8e-8 | 4.2e-10 | MHz T^-1 | false | 42.577 478 461 | 0.000 000 018 |
| proton mag. mom. | 1.41060679545e-26 | 6e-36 | 4.3e-10 | J T^-1 | false | 1.410 606 795 45 e-26 | 0.000 000 000 60 e-26 |
| proton mag. mom. to Bohr magneton ratio | 0.0015210322023 | 4.5e-13 | 3e-10 | false | 1.521 032 202 30 e-3 | 0.000 000 000 45 e-3 | |
| proton mag. mom. to nuclear magneton ratio | 2.79284734463 | 8.2e-10 | 2.9e-10 | false | 2.792 847 344 63 | 0.000 000 000 82 | |
| proton mag. shielding correction | 0.0000256715 | 4.1e-9 | 0.00016 | false | 2.567 15 e-5 | 0.000 41 e-5 | |
| proton mass | 1.67262192595e-27 | 5.2e-37 | 3.1e-10 | kg | false | 1.672 621 925 95 e-27 | 0.000 000 000 52 e-27 |
| proton mass energy equivalent | 1.50327761802e-10 | 4.7e-20 | 3.1e-10 | J | false | 1.503 277 618 02 e-10 | 0.000 000 000 47 e-10 |
| proton mass energy equivalent in MeV | 938.27208943 | 2.9e-7 | 3.1e-10 | MeV | false | 938.272 089 43 | 0.000 000 29 |
| proton mass in u | 1.0072764665789 | 8.3e-12 | 8.2e-12 | u | false | 1.007 276 466 5789 | 0.000 000 000 0083 |
| proton molar mass | 0.00100727646764 | 3.1e-13 | 3.1e-10 | kg mol^-1 | false | 1.007 276 467 64 e-3 | 0.000 000 000 31 e-3 |
| proton relative atomic mass | 1.0072764665789 | 8.3e-12 | 8.2e-12 | false | 1.007 276 466 5789 | 0.000 000 000 0083 | |
| proton rms charge radius | 8.4075e-16 | 6.4e-19 | 0.00076 | m | false | 8.4075 e-16 | 0.0064 e-16 |
| proton-electron mass ratio | 1836.152673426 | 3.2e-8 | 1.7e-11 | false | 1836.152 673 426 | 0.000 000 032 | |
| proton-muon mass ratio | 8.88024338 | 2e-7 | 2.3e-8 | false | 8.880 243 38 | 0.000 000 20 | |
| proton-neutron mag. mom. ratio | -1.45989802 | 3.4e-7 | 2.3e-7 | false | -1.459 898 02 | 0.000 000 34 | |
| proton-neutron mass ratio | 0.99862347797 | 4e-10 | 4e-10 | false | 0.998 623 477 97 | 0.000 000 000 40 | |
| proton-tau mass ratio | 0.528051 | 0.000036 | 0.000068 | false | 0.528 051 | 0.000 036 | |
| quantum of circulation | 0.00036369475467 | 1.1e-13 | 3e-10 | m^2 s^-1 | false | 3.636 947 5467 e-4 | 0.000 000 0011 e-4 |
| quantum of circulation times 2 | 0.00072738950934 | 2.3e-13 | 3.2e-10 | m^2 s^-1 | false | 7.273 895 0934 e-4 | 0.000 000 0023 e-4 |
| reduced Compton wavelength | 3.8615926744e-13 | 1.2e-22 | 3.1e-10 | m | false | 3.861 592 6744 e-13 | 0.000 000 0012 e-13 |
| reduced Planck constant | 1.054571817e-34 | 0 | 0 | J s | true | 1.054 571 817... e-34 | (exact) |
| reduced Planck constant in eV s | 6.582119569e-16 | 0 | 0 | eV s | true | 6.582 119 569... e-16 | (exact) |
| reduced Planck constant times c in MeV fm | 197.3269804 | 0 | 0 | MeV fm | true | 197.326 980 4... | (exact) |
| reduced muon Compton wavelength | 1.867594306e-15 | 4.2e-23 | 2.2e-8 | m | false | 1.867 594 306 e-15 | 0.000 000 042 e-15 |
| reduced neutron Compton wavelength | 2.100194152e-16 | 1.1e-25 | 5.2e-10 | m | false | 2.100 194 1520 e-16 | 0.000 000 0011 e-16 |
| reduced proton Compton wavelength | 2.10308910051e-16 | 6.6e-26 | 3.1e-10 | m | false | 2.103 089 100 51 e-16 | 0.000 000 000 66 e-16 |
| reduced tau Compton wavelength | 1.110538e-16 | 7.5e-21 | 0.000068 | m | false | 1.110 538 e-16 | 0.000 075 e-16 |
| second radiation constant | 0.01438776877 | 0 | 0 | m K | true | 1.438 776 877... e-2 | (exact) |
| shielded helion gyromag. ratio | 203789460.78 | 0.18 | 8.8e-10 | s^-1 T^-1 | false | 2.037 894 6078 e8 | 0.000 000 0018 e8 |
| shielded helion gyromag. ratio in MHz/T | 32.434100033 | 2.8e-8 | 8.6e-10 | MHz T^-1 | false | 32.434 100 033 | 0.000 000 028 |
| shielded helion mag. mom. | -1.07455311035e-26 | 9.3e-36 | 8.7e-10 | J T^-1 | false | -1.074 553 110 35 e-26 | 0.000 000 000 93 e-26 |
| shielded helion mag. mom. to Bohr magneton ratio | -0.00115867149457 | 9.4e-13 | 8.1e-10 | false | -1.158 671 494 57 e-3 | 0.000 000 000 94 e-3 | |
| shielded helion mag. mom. to nuclear magneton ratio | -2.1274977624 | 1.7e-9 | 8e-10 | false | -2.127 497 7624 | 0.000 000 0017 | |
| shielded helion to proton mag. mom. ratio | -0.76176657721 | 6.6e-10 | 8.7e-10 | false | -0.761 766 577 21 | 0.000 000 000 66 | |
| shielded helion to shielded proton mag. mom. ratio | -0.7617861334 | 3.1e-9 | 4.1e-9 | false | -0.761 786 1334 | 0.000 000 0031 | |
| shielded proton gyromag. ratio | 267515319.4 | 1.1 | 4.1e-9 | s^-1 T^-1 | false | 2.675 153 194 e8 | 0.000 000 011 e8 |
| shielded proton gyromag. ratio in MHz/T | 42.57638543 | 1.7e-7 | 4e-9 | MHz T^-1 | false | 42.576 385 43 | 0.000 000 17 |
| shielded proton mag. mom. | 1.410570583e-26 | 5.8e-35 | 4.1e-9 | J T^-1 | false | 1.410 570 5830 e-26 | 0.000 000 0058 e-26 |
| shielded proton mag. mom. to Bohr magneton ratio | 0.0015209931551 | 6.2e-12 | 4.1e-9 | false | 1.520 993 1551 e-3 | 0.000 000 0062 e-3 | |
| shielded proton mag. mom. to nuclear magneton ratio | 2.792775648 | 1.1e-8 | 3.9e-9 | false | 2.792 775 648 | 0.000 000 011 | |
| shielding difference of d and p in HD | 1.9877e-8 | 1e-12 | 0.00005 | false | 1.987 70 e-8 | 0.000 10 e-8 | |
| shielding difference of t and p in HT | 2.3945e-8 | 2e-12 | 0.000084 | false | 2.394 50 e-8 | 0.000 20 e-8 | |
| speed of light in vacuum | 299792458 | 0 | 0 | m s^-1 | true | 299 792 458 | (exact) |
| standard acceleration of gravity | 9.80665 | 0 | 0 | m s^-2 | true | 9.806 65 | (exact) |
| standard atmosphere | 101325 | 0 | 0 | Pa | true | 101 325 | (exact) |
| standard-state pressure | 100000 | 0 | 0 | Pa | true | 100 000 | (exact) |
| tau Compton wavelength | 6.97771e-16 | 4.7e-20 | 0.000067 | m | false | 6.977 71 e-16 | 0.000 47 e-16 |
| tau energy equivalent | 1776.86 | 0.12 | 0.000068 | MeV | false | 1776.86 | 0.12 |
| tau mass | 3.16754e-27 | 2.1e-31 | 0.000066 | kg | false | 3.167 54 e-27 | 0.000 21 e-27 |
| tau mass energy equivalent | 2.84684e-10 | 1.9e-14 | 0.000067 | J | false | 2.846 84 e-10 | 0.000 19 e-10 |
| tau mass in u | 1.90754 | 0.00013 | 0.000068 | u | false | 1.907 54 | 0.000 13 |
| tau molar mass | 0.00190754 | 1.3e-7 | 0.000068 | kg mol^-1 | false | 1.907 54 e-3 | 0.000 13 e-3 |
| tau-electron mass ratio | 3477.23 | 0.23 | 0.000066 | false | 3477.23 | 0.23 | |
| tau-muon mass ratio | 16.817 | 0.0011 | 0.000065 | false | 16.8170 | 0.0011 | |
| tau-neutron mass ratio | 1.89115 | 0.00013 | 0.000069 | false | 1.891 15 | 0.000 13 | |
| tau-proton mass ratio | 1.89376 | 0.00013 | 0.000069 | false | 1.893 76 | 0.000 13 | |
| triton g factor | 5.95792493 | 1.2e-8 | 2e-9 | false | 5.957 924 930 | 0.000 000 012 | |
| triton mag. mom. | 1.5046095178e-26 | 3e-35 | 2e-9 | J T^-1 | false | 1.504 609 5178 e-26 | 0.000 000 0030 e-26 |
| triton mag. mom. to Bohr magneton ratio | 0.0016223936648 | 3.2e-12 | 2e-9 | false | 1.622 393 6648 e-3 | 0.000 000 0032 e-3 | |
| triton mag. mom. to nuclear magneton ratio | 2.978962465 | 5.9e-9 | 2e-9 | false | 2.978 962 4650 | 0.000 000 0059 | |
| triton mass | 5.0073567512e-27 | 1.6e-36 | 3.2e-10 | kg | false | 5.007 356 7512 e-27 | 0.000 000 0016 e-27 |
| triton mass energy equivalent | 4.5003878119e-10 | 1.4e-19 | 3.1e-10 | J | false | 4.500 387 8119 e-10 | 0.000 000 0014 e-10 |
| triton mass energy equivalent in MeV | 2808.92113668 | 8.8e-7 | 3.1e-10 | MeV | false | 2808.921 136 68 | 0.000 000 88 |
| triton mass in u | 3.01550071597 | 1e-10 | 3.3e-11 | u | false | 3.015 500 715 97 | 0.000 000 000 10 |
| triton molar mass | 0.00301550071913 | 9.4e-13 | 3.1e-10 | kg mol^-1 | false | 3.015 500 719 13 e-3 | 0.000 000 000 94 e-3 |
| triton relative atomic mass | 3.01550071597 | 1e-10 | 3.3e-11 | false | 3.015 500 715 97 | 0.000 000 000 10 | |
| triton to proton mag. mom. ratio | 1.0666399189 | 2.1e-9 | 2e-9 | false | 1.066 639 9189 | 0.000 000 0021 | |
| triton-electron mass ratio | 5496.92153551 | 2.1e-7 | 3.8e-11 | false | 5496.921 535 51 | 0.000 000 21 | |
| triton-proton mass ratio | 2.99371703403 | 1e-10 | 3.3e-11 | false | 2.993 717 034 03 | 0.000 000 000 10 | |
| unified atomic mass unit | 1.66053906892e-27 | 5.2e-37 | 3.1e-10 | kg | false | 1.660 539 068 92 e-27 | 0.000 000 000 52 e-27 |
| vacuum electric permittivity | 8.8541878188e-12 | 1.4e-21 | 1.6e-10 | F m^-1 | false | 8.854 187 8188 e-12 | 0.000 000 0014 e-12 |
| vacuum mag. permeability | 0.00000125663706127 | 2e-16 | 1.6e-10 | N A^-2 | false | 1.256 637 061 27 e-6 | 0.000 000 000 20 e-6 |
| von Klitzing constant | 25812.80745 | 0 | 0 | ohm | true | 25 812.807 45... | (exact) |
| weak mixing angle | 0.22305 | 0.00023 | 0.001 | false | 0.223 05 | 0.000 23 |