Kilometer to Light Year Converter

About this conversion

The kilometer (km) is a unit of length in the metric (SI), commonly used for road and highway distances and geographic measurements. The light-year (ly) belongs to the astronomical and is typically found in measurements related to distances to nearby stars and sizes of galaxies. By definition, one kilometer is one thousand meters. One light-year is the distance light travels in one Julian year in a vacuum, approximately 9.461 × 10¹⁵ meters. The conversion factor between these two units is 1.0570042385869967e-13: multiplying any value in km by this number gives the equivalent in ly. For example, 10 km equals 0.0000 ly. Going the other direction, 1 ly equals 9460700000000 km. Adopted alongside the metric system, the kilometer became the standard unit for land distance in most countries by the 20th century.