Speed Converter
Convert between km/h, mph, m/s, ft/s, knots and Mach
How Speed Conversion Works
Speed measures distance traveled per unit of time. Different fields use different units: road traffic (km/h, mph), science (m/s), aviation and marine (knots), and aerospace (Mach).
Common Speed Units
- km/h: Kilometers per hour, used in most countries for road speed.
- mph: Miles per hour, used in the US and UK for road speed.
- m/s: Meters per second, the SI unit of speed.
- Knots: Nautical miles per hour, used in aviation and maritime.
- Mach: Ratio of speed to the speed of sound (~343 m/s at sea level).
Frequently Asked Questions
How do you convert km/h to mph?
Divide km/h by 1.60934 to get mph. Example: 100 km/h = 62.14 mph.
What is Mach 1?
Mach 1 is the speed of sound, approximately 343 m/s or 1,235 km/h at sea level and 20°C.
What is a knot?
A knot equals one nautical mile per hour (1.852 km/h). Used in aviation and maritime navigation.
How fast is the speed of light?
About 299,792,458 m/s or roughly 1,079,252,849 km/h.