Length Converters

Convert between metric and imperial length units: centimeters, inches, meters, feet, kilometers, miles, millimeters, and yards.

Length converter

1 cm = 0.393701 in

All length converters

About length units

Length measures distance, and two systems dominate everyday use. The metric system (millimeter, centimeter, meter, kilometer) is decimal — each step is a factor of ten — and is the standard almost everywhere for science, engineering, and daily life. The imperial and US customary system (inch, foot, yard, mile) survives in the United States and, for specific uses like road distances and personal height, in the United Kingdom.

Since the International Yard and Pound Agreement of 1959, the two systems are locked together exactly: one inch is defined as 2.54 centimeters, one yard as 0.9144 meters. Every converter on this page uses those exact legal definitions, so results are limited only by display rounding — never by an approximate factor.