Speed Converter
Convert between kilometers per hour, miles per hour, meters per second, knots, feet per second, and Mach. Useful for driving, aviation, maritime, and physics.
Common Speed Conversions
| From | To |
|---|---|
| 1 m/s | 3.6 km/h |
| 1 m/s | 2.23694 mph |
| 1 m/s | 1.94384 knots |
| 1 km/h | 0.621371 mph |
| 1 km/h | 0.27778 m/s |
| 1 mph | 1.60934 km/h |
| 1 mph | 0.44704 m/s |
| 1 knot | 1.852 km/h |
| 1 knot | 1.15078 mph |
| Mach 1 (sea level) | 340.29 m/s = 1,225 km/h = 761.2 mph |
Speed Unit Definitions
- Meter per second (m/s)
- The SI unit of speed. Used in physics and science.
- Kilometer per hour (km/h)
- Standard speed unit for road traffic in most countries.
- Mile per hour (mph)
- Used in the US, UK, and some other countries for road speed.
- Knot (kt)
- 1 nautical mile per hour = 1.852 km/h. Used in aviation and maritime navigation.
- Mach
- Ratio of speed to the local speed of sound (~340 m/s at sea level, 20 °C).
Frequently Asked Questions
How do I convert km/h to mph?
Multiply km/h by 0.621371. Example: 100 km/h × 0.621371 = 62.14 mph.
What is a knot in km/h?
One knot equals exactly 1.852 km/h or approximately 1.15078 mph.
How fast is Mach 1 in km/h?
At sea level and 20 °C, Mach 1 ≈ 1,225 km/h (761 mph). The speed of sound varies with temperature and altitude.