Speed Converter
Convert speed units: km/h, mph, m/s and knots.
Speed conversions between km/h, m/s, mph, knots, and Mach number are needed in physics, engineering, aviation, weather reporting, and everyday driving contexts. This converter handles all common speed units and includes real-world reference points to put any speed in context — from a walking pace to the speed of light.
📋 How to Use This Calculator
Enter a speed value in any unit and all equivalents appear instantly. The reference table shows familiar speeds for context: walking (5 km/h), cycling (20 km/h), highway driving (100 km/h), commercial aircraft (900 km/h), speed of sound (1,235 km/h at sea level), and speed of light (1,079,252,848 km/h).
💡 Key Facts & Information
Key conversions: 1 km/h = 0.2778 m/s = 0.6214 mph = 0.5400 knots. 1 mph = 1.609 km/h = 0.4470 m/s. 1 knot = 1.852 km/h (nautical mile per hour). 1 m/s = 3.6 km/h. Mach 1 (speed of sound) = 1,235 km/h at sea level, 20°C (varies with altitude and temperature — drops to ~1,062 km/h at 10,000m altitude where commercial aircraft fly). Indian road speed limits: expressways 120 km/h, national highways 100 km/h, urban roads 50–80 km/h. Wind speed: Beaufort Scale — calm (<1 km/h), light breeze (12–19 km/h), strong breeze (39–49 km/h), storm (88–102 km/h), hurricane (>118 km/h).