Uncertainty should be read as 1.234(56) = 1.234${\displaystyle \pm }$0.056

Name	Symbol	Value	Units	Relative Uncertainty
Speed of light (in vacuum)	${\displaystyle c}$	${\displaystyle 299\ 792\ 458}$	${\displaystyle \mathrm {m} \ \mathrm {s} ^{-1}}$	(exact)
Magnetic Constant	${\displaystyle \mu _{0}}$	${\displaystyle 4\pi \times 10^{-7}\approx 12.566\ 370\ 6\times 10^{-7}}$	${\displaystyle \mathrm {N} \ \mathrm {A} ^{-2}}$	(exact)
Electric Constant	${\displaystyle \varepsilon _{0}=1/\left(\mu _{0}c^{2}\right)}$	${\displaystyle \approx 8.854\ 187\ 817\times 10^{-12}}$	${\displaystyle \mathrm {F} \ \mathrm {m} ^{-1}}$	(exact)
Newtonian Gravitaional Constant	${\displaystyle G}$	${\displaystyle 6.674\ 2(10)\times 10^{-11}}$	${\displaystyle \mathrm {m} ^{3}\ \mathrm {kg} ^{-1}\ \mathrm {s} ^{-2}}$	${\displaystyle 1.5\times 10^{-4}}$
Plank's Constant	${\displaystyle h}$	${\displaystyle 6.626\ 069\ 3(11)\times 10^{-34}}$	${\displaystyle \mathrm {J} \ \mathrm {s} }$	${\displaystyle 1.7\times 10^{-7}}$
Elementary charge	${\displaystyle e}$	${\displaystyle 1.602\ 176\ 53(14)\times 10^{-19}}$	${\displaystyle \mathrm {C} }$	${\displaystyle 8.5\times 10^{-8}}$
Mass of the electron	${\displaystyle m_{e}}$	${\displaystyle 9.109\ 382\ 6(16)\times 10^{-31}}$	${\displaystyle \mathrm {kg} }$	${\displaystyle 1.7\times 10^{-7}}$
Mass of the proton	${\displaystyle m_{p}}$	${\displaystyle 1.672\ 621\ 71(29)\times 10^{-27}}$	${\displaystyle \mathrm {kg} }$	${\displaystyle 1.7\times 10^{-7}}$
Fine structure constant	${\displaystyle \alpha ={\frac {e^{2}}{4\pi \varepsilon _{0}\hbar c}}}$	${\displaystyle 7.297\ 352\ 568(24)\times 10^{-3}}$	dimensionless	${\displaystyle 3.3\times 10^{-9}}$
Molar gass constant	${\displaystyle R}$	${\displaystyle 8.314\ 472(15)}$	${\displaystyle \mathrm {J} \ \mathrm {mol} ^{-1}\ \mathrm {K} ^{-1}}$	${\displaystyle 1.7\times 10^{-6}}$
Boltzmann's constant	${\displaystyle k}$	${\displaystyle 1.380\ 650\ 5(24)\times 10^{-23}}$	${\displaystyle \mathrm {J} \ \mathrm {K} ^{-1}}$	${\displaystyle 1.8\times 10^{-6}}$
Avogadro's Number	${\displaystyle N_{\text{A}},L}$	${\displaystyle 6.022\ 141\ 5(10)\times 10^{23}}$	${\displaystyle \mathrm {mol} ^{-1}}$	${\displaystyle 1.7\times 10^{-7}}$
Rydberg constant	${\displaystyle R_{\infty }}$	${\displaystyle 10\ 973\ 731.568\ 525(73)}$	${\displaystyle \mathrm {m} ^{-1}}$	${\displaystyle 6.6\times 10^{-12}}$
Standard acceleration of gravity	${\displaystyle g}$	${\displaystyle 9.806\ 65}$	${\displaystyle \mathrm {m} \ \mathrm {s} ^{-2}}$	defined
Atmospheric pressure	${\displaystyle \mathrm {atm} }$	${\displaystyle 101\ 325}$	${\displaystyle \mathrm {Pa} }$	defined
Bohr Radius	${\displaystyle a_{0}\ }$	${\displaystyle 0.529\ 177\ 208\ 59(36)\times 10^{-10}\ }$	${\displaystyle \mathrm {m} \ }$	${\displaystyle 6.8\times 10^{-10}}$
Electron Volt	${\displaystyle eV}$	${\displaystyle 1.602\ 176\ 53(14)\times 10^{-19}}$	${\displaystyle \mathrm {J} }$	${\displaystyle 8.7\times 10^{-8}}$
Luminous efficacy of monochromatic radiation	${\displaystyle K_{cd}}$	${\displaystyle 683}$	${\displaystyle \mathrm {lm/W} }$	(exact)
hyperfine transition frequency of Cs-133	${\displaystyle \Delta \nu _{\text{Cs}}}$	${\displaystyle 9\ 192\ 631\ 770}$	${\displaystyle \mathrm {Hz} }$	(exact)
Reduced Planck constant	${\displaystyle \hbar =h/2\pi }$	${\displaystyle 1.054\ 571\ 817\times {10}^{-34}}$	${\displaystyle \mathrm {J} \cdot \mathrm {s} }$	(exact)
atomic mass of Carbon 12	${\displaystyle m({}^{12}{\text{C}})}$	${\displaystyle 1.992\ 646\ 879\ 92(60)\times {10}^{-26}}$	${\displaystyle \mathrm {kg} }$
molar mass of Carbon-12	${\displaystyle M({}^{12}{\text{C}})=N_{\text{A}}m({}^{12}{\text{C}})}$	${\displaystyle 11.999\ 999\ 9958(36)\times {10}^{-3}}$	${\displaystyle \mathrm {kg\cdot {mol}^{-1}} }$
atomic mass constant	${\displaystyle m_{\text{u}}=m({}^{12}{\text{C}})/12=1\,{\text{Da}}}$	${\displaystyle 1.660\ 539\ 066\ 60(50)\times {10}^{-27}}$	${\displaystyle \mathrm {kg} }$
molar mass constant	${\displaystyle M_{\text{u}}=M({}^{12}{\text{C}})/12=N_{\text{A}}m_{\text{u}}}$	${\displaystyle 0.999\ 999\ 999\ 65(30)\times {10}^{-3}}$	${\displaystyle \mathrm {kg\cdot {mol}^{-1}} }$
molar volume of silicon	${\displaystyle V_{m}(\mathrm {Si} )}$	${\displaystyle 1.205\ 883\ 199(60)\times {10}^{-5}}$	${\displaystyle \mathrm {m^{3}\cdot {mol}^{-1}} }$
molar Planck constant	${\displaystyle N_{\text{A}}h}$	${\displaystyle 3.990\ 312\ 712\ldots {10}^{-10}}$	${\displaystyle \mathrm {J\cdot {Hz}^{-1}\cdot {mol}^{-1}} }$
Stefan-Boltzmann constant	${\displaystyle \sigma =\pi ^{2}k_{B}^{4}/60\hbar ^{3}c^{2}}$	${\displaystyle 5.670\ 374\ 419\ldots \times {10}^{-8}}$	${\displaystyle \mathrm {W\cdot m^{-2}\cdot K^{-4}} }$
first radiation constant	${\displaystyle c_{1}=2\pi hc^{2}}$	${\displaystyle 3.741\ 771\ 852\ldots {10}^{-16}}$	${\displaystyle \mathrm {W\cdot m^{2}} }$
first radiation constant for spectral radiance	${\displaystyle c_{\text{1L}}=2hc^{2}/sr}$[1]	${\displaystyle 1.191\ 042\ 972\ 397\ 188\ 414\ 079\ 4892\times {10}^{-16}}$	${\displaystyle \mathrm {W\cdot m^{2}{sr}^{-1}} }$
second radiation constant	${\displaystyle c_{2}=hc/k_{B}}$	${\displaystyle 1.438\ 776\ 877\ldots \times {10}^{-2}}$	${\displaystyle \mathrm {m\cdot K} }$
Wien wavelength displacement constant	${\displaystyle b}$	${\displaystyle 2.897\ 771\ 955\ldots \times {10}^{-3}}$	${\displaystyle \mathrm {m\cdot K} }$
Wien frequency displacement constant	${\displaystyle b'=c/b}$	${\displaystyle 5.878\ 925\ 757\ \times {10}^{10}}$	${\displaystyle \mathrm {Hz\cdot K^{-1}} }$
Wien entropy displacement constant	${\displaystyle b_{\text{entropy}}}$	${\displaystyle 3.002\ 916\ 077\ldots \times {10}^{-3}}$	${\displaystyle \mathrm {m\cdot K} }$
Faraday constant	${\displaystyle F=N_{\text{A}}e}$[2]	${\displaystyle 96\ 485.332\ 123\ 310\ 0184}$	${\displaystyle \mathrm {C\cdot {mol}^{-1}} }$

This list is prepared in the format

• Constant (symbol) : value

• Coulomb's Law Constant (k) : 1/(4 π ε₀) = 9.0 × 10⁹ N·m²/C²
• Faraday constant (F)  : 96,485 C·mol⁻¹
• Mass of a neutron (m_n) : 1.67495 × 10⁻²⁷ kg
• Mass of Earth : 5.98 × 10²⁴ kg
• Mass of the Moon : 7.35 × 10²² kg
• Mean radius of Earth : 6.37 × 10⁶ m
• Mean radius of the Moon : 1.74 × 10⁶ m
• Dirac's Constant (${\displaystyle \hbar }$) : ${\displaystyle h/(2\pi )}$ = 1.05457148 × 10⁻³⁴ J·s
• Speed of sound in air at STP : 3.31 × 10² m/s
• Unified Atomic Mass Unit (u) : 1.66 × 10⁻²⁷ kg

• Wikipedia Article

• NIST Physics Lab

1. ↑ "first radiation constant for spectral radiance". NIST.gov. NIST. Retrieved 5 June 2022.
2. ↑ "Faraday constant". NIST.gov. NIST. Retrieved 5 June 2022.