Speed Converter

Convert speed between m/s, km/h, mph, knots, and Mach.

Calculator

decimal places

Speed is a physical quantity that describes how fast an object moves through space — the ratio of distance traveled to time elapsed.

Main Speed Measurement Units

  • m/s — the SI base unit, standard in science and engineering.
  • km/h — the standard for road and ground transportation.
  • mph (miles per hour) — used in the US, the UK, and a few other countries.
  • Knot — one nautical mile per hour; the standard in maritime navigation and aviation.
  • Mach — the ratio of an object's speed to the speed of sound; used for supersonic speeds.