Speed Converter
Free online speed converter. Convert km/h, mph, m/s, knots, Mach and ft/s instantly.
Convert between km/h, mph, m/s, knots, ft/s, and Mach numbers instantly. Essential for drivers, pilots, mariners, and scientists working across different measurement systems.
Common Speed Conversions
- 1 mph = 1.60934 km/h = 0.44704 m/s
- 1 km/h = 0.62137 mph = 0.27778 m/s
- 1 knot = 1.852 km/h = 1.15078 mph — nautical/aviation
- Mach 1 ≈ 343 m/s = 1,235 km/h at sea level (20°C)
- 1 ft/s = 0.3048 m/s = 1.09728 km/h
Speed in Context
Speed limits on roads are shown in km/h in most countries and in mph in the US and UK. Aviation and maritime navigation use knots. Supersonic aircraft and military jets are often rated in Mach numbers. Scientists prefer m/s as it is the SI unit. Knowing conversions is critical when moving between regions with different systems.