Inch to Kilometer Converter

About this conversion

The inch (in) is a unit of length in the imperial / US customary, commonly used for TV and monitor screen diagonals and US and UK clothing sizes. The kilometer (km) belongs to the metric (SI) and is typically found in measurements related to road and highway distances and geographic measurements. By definition, one inch is exactly 2.54 centimeters, by international agreement since 1959. One kilometer is one thousand meters. The conversion factor between these two units is 0.000025399999999999997: multiplying any value in in by this number gives the equivalent in km. For example, 10 in equals 0.0003 km. Going the other direction, 1 km equals 39370.07874 in. The inch was historically based on the width of a human thumb. Its exact metric equivalent (2.54 cm) was standardized internationally in 1959. Adopted alongside the metric system, the kilometer became the standard unit for land distance in most countries by the 20th century.