Speed Converter
Convert between different speed units including mph, km/h, m/s, knots, and more.
Speed Conversion
Common Speeds
Speed Reference Guide
Common Speed Units
Meters per Second (m/s): SI base unit for speed
Kilometers per Hour (km/h): Common metric unit
Miles per Hour (mph): Imperial unit used in US/UK
Feet per Second (ft/s): Imperial unit for technical use
Knots: Nautical speed (1 knot = 1 nautical mile/hour)
Mach: Speed relative to sound (343 m/s at sea level)
Speed Comparisons
Human walking: ~5 km/h (3.1 mph)
Bicycle: ~20 km/h (12.4 mph)
Car (city): ~50 km/h (31 mph)
Car (highway): ~120 km/h (75 mph)
Commercial jet: ~900 km/h (560 mph)
Sound: 1,235 km/h (767 mph)
Worth Knowing
Nautical Mile vs Mile
A nautical mile is 1,852 metres, about 15 percent longer than the statute mile of 1,609.344 metres, and equals one minute of latitude.
Understanding Speed Conversions
Speed conversions move between kilometers per hour (km/h), miles per hour (mph), meters per second (m/s) and knots. The SI unit is the meter per second, and every other unit is a rescaling of it over a fixed distance and time.
Useful anchors: 1 m/s is 3.6 km/h, and 1 mph is about 1.609 km/h. Knots (nautical miles per hour) are used in aviation and shipping, 1 knot is about 1.852 km/h. When converting a vehicle speed limit, remember the relationship is linear, so 100 km/h is roughly 62 mph.
Frequently Asked Questions
How do I convert km/h to mph?
Divide the km/h value by 1.60934, or multiply by 0.621371. For example, 100 km/h ≈ 62.1 mph.
How many km/h is 1 m/s?
One meter per second equals exactly 3.6 kilometers per hour.
What is a knot in mph?
One knot equals approximately 1.15078 mph (1.852 km/h).
How fast is 60 mph in km/h?
60 mph equals approximately 96.56 km/h.