🚀 Speed Converter
Free online speed converter. Convert between miles per hour, kilometers per hour, meters per second, knots and Mach.
Conversion Reference Table
| Unit | Value |
|---|
Speed Conversion Guide
Speed is measured differently depending on the context. Road speeds use miles per hour (mph) in the US and UK, and kilometers per hour (km/h) almost everywhere else. Aviation and maritime navigation use knots (nautical miles per hour). Physics and engineering use meters per second (m/s). Our speed converter handles all of these.
The conversion between mph and km/h is one of the most searched speed conversions. One mile per hour equals 1.60934 km/h. So the US highway speed limit of 65 mph is approximately 105 km/h. A speed limit of 100 km/h (common in Europe) is approximately 62.1 mph.
Knots and Mach
One knot equals 1.852 km/h or 1.15078 mph. Knots are used in aviation and maritime navigation because they are based on nautical miles, which are tied to the Earth's latitude system. Mach 1 (the speed of sound at sea level) equals approximately 340.29 m/s, 1,225 km/h or 761.2 mph. Commercial aircraft typically cruise at around Mach 0.85, or about 900 km/h.