Speed Converter
Convert speed between km/h, mph, m/s, knots, and feet per second, updated live as you type.
About Speed Converter
A speed converter translates between the units used in different parts of daily life: km/h on European road signs, mph in the US and UK, knots in aviation and maritime contexts, and m/s in physics and weather reports. Comparing a wind speed forecast with a driving limit, or matching a treadmill setting to a running pace, means moving between these systems without error. This tool delivers the answer instantly.
All units convert through meters per second as the reference. Kilometers per hour divide by 3.6 to become m/s, miles per hour multiply by 1.60934 to become km/h, and knots use the nautical mile, so one knot equals 1.852 km/h or 1.15078 mph. Because every conversion passes through one base unit, results stay consistent in any direction, and fractional speeds convert precisely rather than being approximated.
Travelers comparing speed limits while driving abroad, pilots and sailors working with knots, and runners or cyclists converting paces between mph and km/h all use it. Weather enthusiasts comparing wind speeds in different units, physics students checking practice problems, and engineers reviewing specifications will get accurate answers instantly. It turns a confusing tangle of unit conventions into a one-step check.
How to Use
- Enter a speed value.
- Choose the unit you have and the unit you want.
- Get the converted speed instantly, ready to copy.
Example
100 km/h 62.137 mph
One km/h equals 0.621371 mph, so 100 km/h ≈ 62 mph. This is the standard conversion for speed limits and car speeds.
FAQ
What speed units are available?
Meters per second, kilometers per hour, miles per hour, feet per second, and knots.
How do knots relate to mph?
One knot equals 1.15078 mph, because knots are defined relative to the nautical mile while mph uses the statute mile.
Why would I need m/s?
Meters per second is the standard unit in physics, engineering, and weather reporting for wind speed.
Why do pilots use knots instead of mph?
Knots are tied to nautical miles, which relate directly to latitude and longitude, making navigation math simpler over the distances aircraft cover.
How fast is a wind speed of 20 m/s?
That is about 72 km/h or 44.7 mph, which is a strong gale on the Beaufort scale, capable of moving large branches and making walking difficult.