Speed Converter
Convert speed units instantly: meters per second, km/h, mph, knots and feet per second.
Result
Is 100 km/h fast in mph? How strong is a 25-knot wind? What does 10 m/s from a physics problem feel like on a car dashboard? This speed converter answers live as you type, covering meters per second, kilometers per hour, miles per hour, knots and feet per second.
Every factor is an exact definition, not an approximation: 1 mph = 1.609344 km/h (from the international mile), 1 knot = 1.852 km/h (one nautical mile per hour), 1 km/h = 1000/3600 m/s and 1 ft/s = 0.3048 m/s. Results are rounded only for display to sensible significant digits, so conversions are clean in both directions.
The tool runs entirely in your browser — no server, no account, works offline once loaded. Both fields are live and synchronized: type into either one, flip the direction with the swap button, and scan the common-values table under the result, which adapts to the units you chose (city and motorway limits for km/h, wind strengths for knots).
It serves drivers switching between mph and km/h markets, sailors and pilots working in knots, runners and cyclists comparing pace units, and students converting between SI meters per second and the units the rest of the world puts on signs.