Speed & Velocity Converter
Convert between speed units — metres per second (m/s), kilometres per hour (km/h), miles per hour (mph), knots, feet per second (ft/s), centimetres and millimetres per second. Pick any two; it runs entirely in your browser.
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Every factor here is exact, anchored to the metre per second: 1 m/s = 3.6 km/h, 1 km/h = 1/3.6 m/s, 1 mph = 1.609344 km/h, 1 knot = 1.852 km/h, 1 ft/s = 0.3048 m/s. So the live tool and the numbers on every page below always agree.
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Units in this converter
| Unit | What it is |
|---|---|
| Metre per second (m/s) | The SI unit of speed — metres travelled per second. 1 m/s = 3.6 km/h. |
| Kilometre per hour (km/h) | Kilometres per hour — the metric road-speed unit. 1 km/h = 1/3.6 ≈ 0.2778 m/s. |
| Mile per hour (mph) | Miles per hour — the US/UK road-speed unit. 1 mph = 1.609344 km/h = 0.44704 m/s. |
| Foot per second (ft/s) | Feet per second — 1 ft/s = 0.3048 m/s = 1.09728 km/h. |
| Centimetre per second (cm/s) | Centimetres per second — 1 cm/s = 0.01 m/s = 0.036 km/h. |
| Millimetre per second (mm/s) | Millimetres per second — 1 mm/s = 0.001 m/s; used for slow, precise motion (feed rates, fluid flow). |
| Knot (kn) | A knot is one nautical mile per hour — 1 kn = 1.852 km/h = 0.514444 m/s; used in sea and air navigation. |