Speed Converter
Convert between different units of speed and velocity
Convert Speed
Common Speeds
Walking pace
5 km/h | 3 mph
Cycling
20 km/h | 12 mph
City driving
50 km/h | 31 mph
Motorway speed
120 km/h | 75 mph
Commercial jet
900 km/h | 560 mph
Sound in air
343 m/s | Mach 1
Speed Units
Common Units
km/h (kilometres per hour), mph (miles per hour), m/s (metres per second)
Nautical & Aviation
knots (nautical miles per hour), Mach (multiples of sound speed)
Scientific Units
m/s (SI unit), c (speed of light, ~300,000 km/s)
About Speed Conversion
Conversion Relationships
- 1 m/s = 3.6 km/h
- 1 mph = 1.609 km/h
- 1 knot = 1.852 km/h
- 1 ft/s = 0.3048 m/s
- Mach 1 = ~343 m/s (in air at 20°C)
- Speed of light = 299,792,458 m/s
Common Uses
- Transport: Vehicle speeds and speed limits
- Sports: Running, cycling, and racing speeds
- Weather: Wind speeds and storm tracking
Speed Categories
- Subsonic: Less than Mach 1
- Supersonic: Mach 1 to Mach 5
- Hypersonic: Above Mach 5
- Relativistic: Significant fraction of light speed
Technical Notes
- Mach number varies with temperature and altitude
- Knots are used in maritime and aviation
- Results formatted based on magnitude
- Scientific notation used for extreme values