## Conversion of units

This page lists some of the most commonly used non-SI units and their conversion into SI units. Note that all conversion factors are exact according to their international definition, with the exception of the parsec for which an exact numerical representation does not exist. No responsibility is taken for the correctness of the numbers.

### Conversion of cgs units

• Energy:
$1~\mathrm{erg} = 10^{-7}~\mathrm{J}$
• Force:
$1~\mathrm{dyn} = 10^{-5}~\mathrm{N}$
• Magnetic flux density:
$1~\mathrm{G} = 10^{-4}~\mathrm{T}$

### Conversion of U.S. customary units

• Length:
$1~\mathrm{mile} = 1.609344~\mathrm{km}$
$1~\mathrm{yard} = 0.9144~\mathrm{m}$
$1~\mathrm{foot} = 0.3048~\mathrm{m}$
$1~\mathrm{inch} = 2.54~\mathrm{cm}$
• Mass:
$1~\mathrm{ounce} = 28.349523125~\mathrm{g}$
$1~\mathrm{pound} = 0.45359237~\mathrm{kg}$
• Temperature:
$T / ^{\circ}\mathrm{F} = (T / ^{\circ}\mathrm{C}) \times (9 / 5) + 32$

### Conversion of astronomical units

• Distance:
$1~\mathrm{AU} = 1.495978707 \times 10^{11}~\mathrm{m}$
$1~\mathrm{ly} = 9.4607304725808 \times 10^{15}~\mathrm{m}$
$1~\mathrm{pc} = 1~\mathrm{AU} / \tan(1'') \approx 3.08567758146719 \times 10^{16}~\mathrm{m}$
• Flux density:
$1~\mathrm{Jy} = 10^{-26}~\mathrm{W \, m^{-2} \, Hz^{-1}}$