Speed Converter: Convert Between Speed Units

Speed is measured in different units around the world — miles per hour in the US, kilometers per hour in most other countries, and knots for aviation and maritime. Our Speed Converter instantly converts between mph, km/h, knots, meters per second, feet per second, and the speed of light. Whether you are checking speed limits abroad, calculating running pace, or planning a flight, get precise speed conversions.

Key conversions: 1 mph = 1.609 km/h. 1 km/h = 0.621 mph. 1 knot = 1.151 mph = 1.852 km/h. 1 m/s = 2.237 mph. 1 ft/s = 0.682 mph. For running, a 10-minute mile is 6 mph or 9.66 km/h. A 5-minute kilometer is 12 km/h or 7.46 mph. The speed of light is 299,792,458 m/s or about 671 million mph.

Use the Speed Converter for international driving (mph to km/h for rental cars), running pace calculations (mph to min/mile or km/h to min/km), aviation purposes (mph to knots for flight planning), and physics problems (m/s to mph). Also check our Running Pace Calculator for pace-specific calculations and our Length Converter for distance conversions.