Length Converter

Convert between all length and distance units — inches, feet, yards, miles, millimeters, centimeters, meters, kilometers.

Metres are the pivot: your entry is multiplied into metres by its own unit's factor and then divided back out into every other column. All four imperial factors here are exact rather than measured, which is a consequence of the 1959 international yard and pound agreement — the inch was defined as precisely 0.0254 m, making the foot 0.3048 m, the yard 0.9144 m and the mile 1609.344 m. The Feet & Inches column is the one that behaves differently: it takes the whole number of feet, multiplies the leftover fraction by twelve and rounds that remainder to two decimals, so it reads as a carpenter would call it rather than as a decimal. Rounding is not uniform across the table. Millimetres are held to two decimals, centimetres to three, miles and kilometres to five, and the rest to four, so a very short distance can display as a flat zero in the miles column while still showing digits in millimetres. Note the omissions: no nautical mile, no US survey foot, and nothing at astronomical or microscopic scale — no light-years, microns or angstroms. This is strictly one-dimensional, so it will not square or cube anything for you into area or volume.