Commonly Used Physical Constants

Uncertainty should be read as 1.234(56) = 1.234 $\pm$ 0.056
Name	Symbol	Value	Units	Relative Uncertainty
Speed of light (in vacuum)	$c$	$299\ 792\ 458$	$\mathrm {m} \ \mathrm {s} ^{-1}$	(exact)
Magnetic Constant	$\mu _{0}$	$4\pi \times 10^{-7}\approx 12.566\ 370\ 6\times 10^{-7}$	$\mathrm {N} \ \mathrm {A} ^{-2}$	(exact)
Electric Constant	$\varepsilon _{0}=1/\left(\mu _{0}c^{2}\right)$	$\approx 8.854\ 187\ 817\times 10^{-12}$	$\mathrm {F} \ \mathrm {m} ^{-1}$	(exact)
Newtonian Gravitaional Constant	$G$	$6.674\ 2(10)\times 10^{-11}$	$\mathrm {m} ^{3}\ \mathrm {kg} ^{-1}\ \mathrm {s} ^{-2}$	$1.5\times 10^{-4}$
Plank's Constant	$h$	$6.626\ 069\ 3(11)\times 10^{-34}$	$\mathrm {J} \ \mathrm {s}$	$1.7\times 10^{-7}$
Elementary charge	$e$	$1.602\ 176\ 53(14)\times 10^{-19}$	$\mathrm {C}$	$8.5\times 10^{-8}$
Mass of the electron	$m_{e}$	$9.109\ 382\ 6(16)\times 10^{-31}$	$\mathrm {kg}$	$1.7\times 10^{-7}$
Mass of the proton	$m_{p}$	$1.672\ 621\ 71(29)\times 10^{-27}$	$\mathrm {kg}$	$1.7\times 10^{-7}$
Fine structure constant	$\alpha ={\frac {e^{2}}{4\pi \varepsilon _{0}\hbar c}}$	$7.297\ 352\ 568(24)\times 10^{-3}$	dimensionless	$3.3\times 10^{-9}$
Molar gass constant	$R$	$8.314\ 472(15)$	$\mathrm {J} \ \mathrm {mol} ^{-1}\ \mathrm {K} ^{-1}$	$1.7\times 10^{-6}$
Boltzmann's constant	$k$	$1.380\ 650\ 5(24)\times 10^{-23}$	$\mathrm {J} \ \mathrm {K} ^{-1}$	$1.8\times 10^{-6}$
Avogadro's Number	$N_{A}$	$6.022\ 141\ 5(10)\times 10^{23}$	$\mathrm {mol} ^{-1}$	$1.7\times 10^{-7}$
Rydberg constant	$R_{\infty }$	$10\ 973\ 731.568\ 525(73)$	$\mathrm {m} ^{-1}$	$6.6\times 10^{-12}$
Standard acceleration of gravity	$g$	$9.806\ 65$	$\mathrm {m} \ \mathrm {s} ^{-2}$	defined
Atmospheric pressure	$\mathrm {atm}$	$101\ 325$	$\mathrm {Pa}$	defined
Bohr Radius	$a_{0}\$	$0.529\ 177\ 208\ 59(36)\times 10^{-10}\$	$\mathrm {m} \$	$6.8\times 10^{-10}$
Electron Volt	$eV$	$1.602\ 176\ 53(14)\times 10^{-19}$	$\mathrm {J}$	$8.7\times 10^{-8}$