Speed Converter
Convert between units of speed, including kilometers per hour, miles per hour, knots, meters per second and feet per second.
Convert kilometers per hour
Convert miles per hour
Convert meters per second
Convert knots
Convert feet per second
Speed units
- Kilometer per hour (km/h)
- A kilometer per hour is a speed of one kilometer traveled in one hour, exactly 1/3.6 meters per second. It is the unit on road signs and speedometers in most countries.
- Mile per hour (mph)
- A mile per hour is a speed of one international mile (1,609.344 meters) traveled in one hour, exactly 0.44704 meters per second. It is the unit on road signs in the United States and the United Kingdom.
- Meter per second (m/s)
- The meter per second is the SI unit of speed: one meter traveled in one second. It is the standard unit in science and is used for wind speed in many countries.
- Knot (kn)
- A knot is one nautical mile (exactly 1,852 meters) per hour, about 0.5144 meters per second. It is the standard unit of speed in shipping, sailing and aviation.
- Foot per second (ft/s)
- A foot per second is a speed of one international foot (0.3048 meters) traveled in one second. It is used in US engineering and for the muzzle velocity of bullets.
- Mach (Ma)
- A Mach number is the ratio of a speed to the speed of sound in the surrounding air, so Mach 1 is the speed of sound. It is used for the speed of aircraft and rockets.
- Times the speed of light (c)
- The speed of light in a vacuum is exactly 299,792,458 meters per second, a fixed constant that defines the meter. Speeds in physics and astronomy are often given as a fraction of it.