Speed Converter

Convert speed between any units

The Speed Converter converts between the units used for velocity — kilometers per hour, miles per hour, meters per second, knots, and feet per second. Type a value, choose your units, and read the result instantly. Whether you are comparing car speeds across countries, reading a wind forecast, or working through a physics problem, this tool gives accurate answers without manual math.

Where each unit is used

km/h is the everyday speed unit in most of the world, shown on speedometers and road signs. mph is standard in the United States and United Kingdom. m/s is the scientific unit used in physics. Knots (nautical miles per hour) are used in aviation and maritime contexts, and ft/s appears in some engineering and ballistics applications.

Common speed conversions

From	To	Multiply by
km/h	mph	0.6214
mph	km/h	1.6093
m/s	km/h	3.6
knots	km/h	1.852

How to use it

1. Enter a speed in the From field.
2. Select the unit you are converting from and the unit you want.
3. Read the result instantly, or swap to reverse the conversion.

Quick facts about speed

• To roughly convert km/h to mph, multiply by 0.62 (or subtract about a third).
• 1 m/s is exactly 3.6 km/h — handy for physics work.
• A knot is one nautical mile per hour, slightly faster than 1 mph.
• Highway speeds of 100 km/h are about 62 mph.

Private and free

All conversions are computed locally in your browser using exact factors, with nothing uploaded and no limits. Convert as many speeds as you need, completely free.