math
Speed Converter
Convert between speed units — m/s, km/h, mph, knots, and feet per second.
Result
0.621371
1 Kilometre per hour (km/h) = 0.621371 Mile per hour (mph)
How it works
- 1Enter a speed value.
- 2Pick the unit to convert from and the unit to convert to.
- 3Read the result instantly, or press ⇄ to swap units.
Use cases
- Convert km/h to mph for driving abroad.
- Convert knots to km/h for sailing and aviation.
- Convert metres per second to km/h for physics.
Frequently asked questions
How do I convert km/h to mph?
Multiply km/h by 0.621371. For example, 100 km/h ≈ 62.14 mph.
What is a knot?
A knot is one nautical mile per hour, about 1.852 km/h, used in sailing and aviation.
How fast is 1 m/s?
One metre per second equals 3.6 km/h, or about 2.237 mph.
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