Converter hub
Speed Converter
Speed conversions link road, aviation and scientific units. Knots are nautical miles per hour, while Mach depends on the speed of sound in the local medium. Pick a pair below or open the page for the exact factor, a worked example and a full chart.
Units in this category
Speed conversions link road, aviation and scientific units. Knots are nautical miles per hour, while Mach depends on the speed of sound in the local medium.
| Unit | Symbol | Definition |
|---|---|---|
| Kilometers per Hour | km/h | Kilometres per hour is the standard road-speed unit in most of the world. |
| Miles per Hour | mph | Miles per hour is the standard road-speed unit in the US and UK, equal to 1.609344 km/h. |
| Meters per Second | m/s | Metres per second is the SI unit of speed and the basis for scientific measurement. |
| Knots | kn | One knot is one nautical mile per hour, exactly 1.852 km/h. |
All speed conversions
Every listed pair has its own page with the formula, examples and a chart. Choose the starting unit:
Kilometers per Hour (km/h)
Miles per Hour (mph)
Meters per Second (m/s)
Frequently asked questions
How many speed units are supported?
4 units, which gives 8 one-way conversions.
Are the factors exact?
They follow SI and international definitions. Where a unit is approximate by nature (for example Mach, months or fuel economy), the page says so.
Can I convert in both directions?
Yes. Every pair page has a swap link and the calculator accepts any decimal value.