Converters
Speed Converter
Convert km/h, mph, m/s, ft/s, and knots instantly.
About This Tool
Convert a speed between common metric, imperial, road, aviation, and maritime units in your browser. This converter handles kilometers per hour (km/h), miles per hour (mph), meters per second (m/s), feet per second (ft/s), and knots, and shows the same input across every supported unit. It is useful for travel, running and cycling pace references, weather reports, engineering checks, navigation, and comparing specifications that use different speed units.
How To Use It
- Enter a non-negative speed value.
- Choose the unit the value is currently expressed in.
- Choose the speed unit you want to convert to.
- Use Swap to reverse the conversion, or copy the numeric result when needed.
Examples
Kilometers per hour to miles per hour
Enter 100 km/h and convert to mph to get about 62.1371 mph, a common comparison for road speeds.
Miles per hour to kilometers per hour
Enter 60 mph and convert to km/h to get 96.56064 km/h.
Meters per second to kilometers per hour
Enter 10 m/s and convert to km/h to get exactly 36 km/h.
Knots to kilometers per hour
Enter 10 knots and convert to km/h to get 18.52 km/h. Knots are commonly used for marine and aviation speeds.
Useful Notes
How speed conversion works
The converter normalizes each value through meters per second and then converts it to the selected target unit. For example, 1 mph equals exactly 0.44704 m/s, while 1 km/h equals 1/3.6 m/s.
Kilometers per hour and miles per hour
Kilometers per hour are widely used for road speeds in metric-system countries. Miles per hour are commonly used for road speeds in the United States and United Kingdom. One mph equals exactly 1.609344 km/h.
Meters and feet per second
Meters per second are the SI-derived form commonly used in science and engineering. Feet per second appear in some imperial and US customary technical contexts. One foot is exactly 0.3048 meters, so 1 ft/s equals exactly 0.3048 m/s.
What is a knot?
A knot is one nautical mile per hour. Because the international nautical mile is exactly 1,852 meters, one knot equals exactly 1.852 km/h or about 1.15078 mph.
Speed versus velocity
Speed describes how fast something moves and has magnitude only. Velocity also includes direction. This tool converts the numerical magnitude between speed units; it does not calculate or transform a direction vector.
FAQ
How do I convert km/h to mph?
Multiply km/h by about 0.6213711922. For example, 100 km/h is about 62.1371 mph.
How do I convert mph to km/h?
Multiply mph by exactly 1.609344. For example, 60 mph equals 96.56064 km/h.
How many km/h is 1 m/s?
One meter per second equals exactly 3.6 kilometers per hour.
Is a knot the same as mph?
No. One knot is one nautical mile per hour and equals about 1.15078 mph or exactly 1.852 km/h.
Can I convert decimal speed values?
Yes. The converter supports decimal values, such as 5.5 m/s, 27.3 mph, or 12.75 knots.
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