Convert between m/s, km/h, mph, knots, ft/s, and Mach
Enter a speed value to see conversions
Convert between metric and imperial units for length, weight, temperature, and more
Convert between mm, cm, m, km, inches, feet, yards, miles, and nautical miles
Convert between milliseconds, seconds, minutes, hours, days, weeks, months, and years
Convert between L/100km, km/L, MPG (US), and MPG (UK)
Speed Converter is a free online tool that converts velocity measurements between six units: meters per second (m/s), kilometers per hour (km/h), miles per hour (mph), knots, feet per second (ft/s), and Mach number. Whether you are comparing vehicle speeds across different countries, analyzing athletic performance, working in aviation or maritime navigation, or studying physics, this tool provides instant and accurate conversions. The metric system uses meters per second as the SI unit of speed and kilometers per hour for everyday use (road speed limits, vehicle speedometers). Miles per hour is the standard in the United States, the United Kingdom, and a few other countries. Knots (nautical miles per hour) are the universal standard in aviation and maritime navigation. Feet per second is commonly used in ballistics and some engineering contexts. Mach number represents speed relative to the speed of sound (approximately 343 m/s at sea level and 20 degrees Celsius). This converter handles all conversions in real time as you type. Enter any speed value and select your source unit to see the equivalent in all other units simultaneously. All calculations are performed in your browser with no data sent to any server.
Key conversion factors: 1 m/s = 3.6 km/h = 2.237 mph = 1.944 kn 1 km/h = 0.2778 m/s = 0.6214 mph = 0.5400 kn 1 mph = 1.609 km/h = 0.4470 m/s = 0.8690 kn 1 knot = 1.852 km/h = 1.151 mph 1 Mach = 343 m/s = 1235 km/h = 767.3 mph 1 ft/s = 0.3048 m/s = 1.097 km/h Examples: 100 km/h = 62.14 mph = 27.78 m/s = 0.081 Mach 60 mph = 96.56 km/h = 52.14 kn