Inch (in)
The inch (symbol in or ″) is a unit of length equal to 1/12 of a foot or exactly 2.54 centimetres. Historically linked to the breadth of a human thumb or three dry barleycorns laid end to end, its precise value varied across Europe until the International Yard and Pound Agreement of 1959 standardized it internationally. It is commonly used in North America and the UK for screen sizes, pipe diameters, and everyday object dimensions.
Metric
- Kilometre (km)2.54×10⁻⁵
- Metre (m)0.03
- Decimetre (dm)0.25
- Centimetre (cm)2.54
- Millimetre (mm)25.4
- Micrometre (µm)25,400
- Nanometre (nm)25,400,000
- Angstrom (Å)254,000,000
Nautical
- Nautical mile1.37×10⁻⁵
- Fathom0.01
Astronomical
- Parsec (pc)8.23×10⁻¹⁹
- Light year2.68×10⁻¹⁸
- Astronomical unit (AE)1.7×10⁻¹³
- Light minute1.41×10⁻¹²
- Light second8.47×10⁻¹¹