| Description  | Symbol  | Value  | Units  |
| Acceleration due to gravity  | $\mathrm{g}$  | $9.80665 $ | $\mathrm{m/s^2}$ |
| Standard atmosphere  | $\mathrm{atm}$  | $101325 $ | $\mathrm{N/m^2}$  |
| Thermochemical kilocalorie  | $\mathrm{kcal}$  | $4184$  | $\mathrm{J}$  |
| Speed of light in vacuum  | $\mathrm{c}$  | $2.997925 \times 10^8$  | $\mathrm{m/s}$  |
| Electronic charge  | $\mathrm{e}$ | $1.6022 \times 10^{-19}$  | $\mathrm{C}$  |
| Electron charge/mass  | $\mathrm{e / m_e}$ | $1.76 \times 10^{11}$  | $\mathrm{C/kg}$  |
| Permeability of free space  | $\mu_\mathrm{o}$  | $1.26 \times 10^{-6}$  | $\mathrm{H/m}$  |
| Permittivity of free space  | $\epsilon_\mathrm{o}$  | $8.8542 \times 10^{-12} $ | $\mathrm{C^2N^{-1}m^{-2}}$ |
| Avogadro constant  | $\mathrm{N_A}$  | $6.0225 \times 10^{26}$  | $\mathrm{kmol^{-1}}$ |
| Faraday constant  | $\mathrm{F}$  | $9.6487 \times 10^7 $ | $\mathrm{C/kmol}$  |
| Rydberg constant  | $\mathrm{R}$  | $1.0974 \times 10^7 $ | $\mathrm{m^{-1}}$  |
| Planck constant  | $\mathrm{h}$ | $6.6262 \times 10^{-34} $ | $\mathrm{Js}$  |
| | | $4.1356 \times 10^{-15}$  | $\mathrm{eV s}$ |
| Bohr magneton ($\mathrm{eh}/4\pi \mathrm{m}_e$)  | $\mu_\mathrm{B}$  | $9.2732 \times 10^{-24}$  | $\mathrm{Am^2}$ |
| Nuclear magneton ($\mathrm{e}\mathrm{h}/4\pi \mathrm{m}_p$)  | $\mu_\mathrm{N}$  | $5.0505 \times 10^{-27}$  | $\mathrm{Am^2}$ |
| Universal gas constant  | $\mathrm{R}$  | $8314$  | $\mathrm{JK/kmol}$  |
| | | $1.987 $ | $\mathrm{kcal\;K/kmol}$  |
| Ideal gas normal volume (STP) | | $22.414$  | $\mathrm{m^3/kmol}$  |
| Boltzmann constant  | $\mathrm{k}$  | $1.3805 \times 10^{-23} $ | $\mathrm{J/K}$   |
| Wien displacement constant  | $\mathrm{A}$  | $2.8978 \times 10^{-3}$  | $\mathrm{mK}$  |
| Stefan-Boltzmann constant  | $\sigma$  | $5.670 \times 10^{-8}$  |$\mathrm{Wm^2/K^4}$  |
| Gravitational constant  | $\mathrm{G}$  | $6.67 \times 10^{-11}$  | $\mathrm{N m^2/kg^2}$  |
| Atomic mass unit  | $\mathrm{amu}$  | $1.6604 \times 10^{-27}$  | $\mathrm{kg}$  |
| Rest energy of 1 amu  | | $931.48$  | $\mathrm{MeV}$  |
| Electron volt  | $\mathrm{eV}$  | $1.60210 \times 10^{-19}$  | $\mathrm{J}$  |
| Rest mass of electron | $\mathrm{m_e}$  | $5.48597 \times 10^{-4}$ | $\mathrm{amu}$ |
| |  | $9.1095 \times 10^{-31}$ | $\mathrm{kg}$ |
| | | 0.511006  | $\mathrm{MeV}$ |
| Rest mass of proton | $\mathrm{m_p}$   | 1.0072766  | $\mathrm{amu}$  |
| | |$ 1.6726 \times 10^{-27}$  | $\mathrm{kg}$  |
| | | $938.26$  | $\mathrm{MeV}$  |