Speed Converter
Convert any speed value between meters per second, kilometers per hour, miles per hour, feet per second, and knots.
Enter a value above to see the conversion.
Advertisement
How Speed Conversion Works
All speed units are expressed as a fixed ratio to meters per second — the SI base unit of speed. To convert from unit A to unit B, the value is multiplied by the m/s factor of A, then divided by the m/s factor of B.
result = value × (A_to_ms / B_to_ms)
Example: 100 km/h → mph = 100 × (0.2778 / 0.44704) ≈ 62.14 mph
Key Equivalents
- 1 m/s = 3.6 km/h
- 1 mph = 1.60934 km/h
- 1 knot = 1.852 km/h
Common References
- Walking ≈ 5 km/h
- Highway ≈ 100 km/h
- Sound ≈ 1235 km/h
Speed Units Around the World
Most countries use kilometers per hour (km/h) for road speeds and everyday contexts. The United States and United Kingdom primarily use miles per hour (mph) for road traffic. In physics and engineering, meters per second (m/s) is the standard SI unit.
Knots — nautical miles per hour — are the universal standard in aviation and maritime navigation. One knot equals one nautical mile per hour, and a nautical mile is defined as one minute of arc along a meridian, making it naturally suited to navigation on the curved surface of the Earth.