Speed Converter
mph, km/h, m/s, knots
Enter a value above to see all conversions.
Common Speed References
Walking speed~5 km/h / 3.1 mph
City speed limit50 km/h / 31 mph
Highway speed100–130 km/h / 62–81 mph
Commercial aircraft~900 km/h / ~560 mph
Speed of sound~1,225 km/h (Mach 1)
Speed of light~1.08 billion km/h
Unit Quick Reference
1 mph= 1.60934 km/h = 0.44704 m/s
1 km/h= 0.62137 mph = 0.27778 m/s
1 m/s= 3.6 km/h = 2.23694 mph
1 knot= 1.852 km/h = 1.15078 mph
Mach 1≈ 340.29 m/s ≈ 1,225 km/h
FAQ
How do you convert mph to km/h?
Multiply by 1.60934. So 60 mph = 96.56 km/h, and 100 mph = 160.93 km/h. This is helpful when traveling between countries with different speed limit systems.
What is Mach 1 in km/h?
Mach 1 equals approximately 1,225 km/h (761 mph) at sea level and 15°C. The exact value varies with altitude and air temperature, as sound travels slower in colder or thinner air.