| Quantity | Value | Unit |
| absolute zero | -273.16 | °C |
| acceleration of free fall | 9.80665 | m s-2 |
| Avogadro constant | 6.0221367 E23 | 1 mol-1 |
| base of natural logarithms | 2.718281828 | |
| Bohr magneton | 9.2740154 E-24 | J T-1 |
| Bohr radius | 5.29177249 E-11 | m |
| Boltzmann constant | 1.380658 E-23 | J K-1 |
| classical electron radius | 2.81794092 E-15 | m |
| Dirac's constant | 1.0545887 E-34 | J s |
| elementary charge | 1.60217733 E-19 | C |
| electron mass | 9.1093897 E-31 | kg |
| electron-proton mass ratio | 5.44617013 E-4 | |
| electronvolt | 1.6021892 E-19 | J |
| Faraday constant | 96485.309 | C mol-1 |
| Feigenbaum's constant | 4.669210609102990 | |
| fine-structure constant | 7.29735308 E-3 | |
| first radiation constant | 3.7417749 E-16 | W m2 |
| Newtonian constant of gravitation | 6.67259 E-11 | N m2 kg-2 |
| hydrogen Rydberg number | 1.0967758 E7 | m-1 |
| Josephson frequency-voltage quotient | 4.8359767 E14 | Hz V-1 |
| Loschmidt constant | 2.686763 E25 | m-3 |
| magnetic flux quantum | 2.06783461 E-15 | Wb |
| molar gas constant | 8.314510 | J mol-1 K-1 |
| molar Planck constant | 3.99031323 E-10 | J s mol-1 |
| molar volume of ideal gas | 0.02241410 | m3 mol-1 |
| standard pressure | 101325 | Pa |
| nuclear magneton | 5.0507866 E-27 | J T-1 |
| permeability of vacuum | 12.566370614 E-7 | N A-2 |
| permittivity of vacuum | 8.854187817 E-12 | F m-1 |
| Pi | 3.1415926535897932 | |
| Planck constants | 6.6260755 E-34 | J s |
| Rydberg constant | 10973731.534 | m-1 |
| second radiation constant | 0.01438769 | m K |
| solar constant | 1400 | W m-2 |
| speed of light in vacuum | 299792458 | m s-1 |
| speed of sound in air at STP | 340 | m s-1 |
| Stefan-Boltzmann constant | 5.67051 E-8 | W m-2 K-4 |
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