Speed Converter
Free speed unit converter for km/h, m/s, mph, knots, ft/s, and Mach. Enter a value, pick its unit, and see every conversion in one table.
Last updated:
Input
Input unit
Kilometers per hour（km/h）
Result
Meters per second (m/s)
27.777778m/s
| Unit | Symbol | Converted value |
|---|---|---|
| Meters per second | m/s | 27.777778 |
| Kilometers per hour | km/h | 100 |
| Miles per hour | mph | 62.137119 |
| Knots | kn | 53.99568 |
| Feet per second | ft/s | 91.134442 |
| Mach | M | 0.08163 |
How it works
- Supports six units: meters per second (m/s), kilometers per hour (km/h), miles per hour (mph), knots (kn), feet per second (ft/s), and Mach (M).
- Meters per second (m/s) is the base unit. Your input is first converted to m/s and then to every other unit. km/h is divided by 3.6 to get m/s, a knot is one nautical mile per hour (1852 m/h), and mph uses 1 mi = 1609.344 m.
- Mach is measured relative to the speed of sound, which changes with air temperature and altitude. This tool treats 1 Mach as the standard sea-level speed of sound at 15°C, roughly 340.29 m/s.
- To use it, enter the number you want to convert and pick its unit from the dropdown. As soon as you select a unit, the results for every unit appear in the table.
- Results are rounded to about six significant digits, and very large or very small numbers switch to scientific notation. Values are approximate, so double-check the original definitions for precise or official use.
Frequently asked questions
- How do you convert km/h to m/s?
- Meters per second (m/s) is the base unit, and you divide km/h by 3.6 to get m/s — for example, 36 km/h equals 10 m/s. Every value is routed through m/s before being converted to the other units.
- What is the difference between a knot and miles per hour?
- A knot (kn) is one nautical mile per hour, or 1852 m/h, and is used at sea and in aviation, while mph is based on the statute mile of 1609.344 m. So the same number of knots is faster than the same number of mph.
- How fast is Mach 1 in km/h, and is the speed of sound fixed?
- This tool uses the standard sea-level speed of sound at 15°C, about 340.29 m/s, as Mach 1, which is roughly 1225 km/h. The real speed of sound changes with air temperature and altitude, so treat Mach values as an approximation.
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