| Constant | Symbol | Value |
| acceleration due to gravity/ standard acceleration of free fall | g | 9.80665 m s-2 |
| atomic mass constant (unified atomic mass unit) | amu, mu or u | 1.6605 x10-27 kg |
| Avogadro's Number/constant | NA | 6.022137 x 1023 mol-1 |
| Bohr magneton | μB | 5.788 × 10-11MeV T--1 |
| Bohr radius | a0 = 4πε0h2/mee2 | 5.29177 × 10-11 m |
| Boltzmann constant | k | 1.38066 × 10-23 J K-1 |
| electron rest mass | me | 9.109 x 10-31 kg |
| charge on an electron | e | - 1.6022 × 10-19 C |
| electron charge to mass ratio | -e/me | -1.7588 x 1011 C kg-1 |
| classical electron radius | re | 2.818 x 10-15 m |
| electron mass energy | mec2 | 8.187 x 10-14 J |
| electron mass energy | mec2 | 0.511 MeV |
| Faraday constant | F | 9.649 x 104 C mol-1 |
| fine-structure constant | α | 7.297 x 10-3 |
| Universal gas constant | R | 8.314 J K-1 mol-1 |
| gravitational constant | G | 6.6738 × 10--11 N (m/kg)2 |
| Lande g-factor for free electron | ge = 2μe/μB | 2.002319 |
| neutron mass energy | mnc2 | 1.505 x 10-10 J |
| neutron mass energy | mnc2 | 939.565 MeV |
| neutron rest mass | mn | 1.675 x 10--27 kg |
| neutron-electron mass ratio | mn/me | 1838.68 |
| neutron-proton mass ratio | mn/mp | 1.0014 |
| nuclear magneton | μN | 3.152 × 10-14 MeV T-1 |
| permeability of vacuum | μ0 | 4π x 10-7 N A-2 |
| permittivity of a vacuum | ε0 | 8.854 x 10-12 F m-1 |
| Planck constant | h | 6.626 x 10-34 J s |
| Planck constant, reduced | h/2π | 1.0546 × 10-34 J s |
| proton mass energy | mpc2 | 1.503 x 10-10 J |
| proton mass energy | mpc2 | 938.272 MeV |
| proton rest mass | mp | 1.6726 x 10-27 kg |
| proton-electron mass ratio | mp/me | 1836.15 |
| Rydberg constant | R∞ = Eh/2hc0 | 1.0974 x 107 m-1 |
| speed of light in vacuum | C | 2.9979 x 108 m/s |
| Stefan-Boltzmann constant | σ0 | 5.6704 × 10-8 W m-2 K-4 |
| Wien’s constant | C3 = λmax ∙ T | 2.8978 × 10-3 m K |
| Electron-volt | eV | 1.602 × 10-19 J |