permittivity of vacuum

Fundamental physical constant $ɛ 0 = 1 μ 0 c 0 2$ exactly, where $μ 0$ is the permeability of vacuum and $c 0$ the speed of light in vacuum. It is equal to $8.854 187 817 ... × 10 −12 F m −1$ .

Source:

CODATA 2006

Green Book, 2nd ed., p. 14