Miles per Hour to Meters per Second

Miles per hour and meters per second

A mile per hour is one international mile per hour: exactly 0.44704 m/s, or 1.609344 km/h. Speed limits and speedometers in the US and UK, and pitch speeds in baseball, use mph.

The meter per second is the SI unit of speed: one meter traveled each second, which is exactly 3.6 km/h. Physics, engineering and wind speeds in scientific forecasts are given in meters per second.

Worked example

Convert 60 mph: 60 × 0.44704 = 26.8224, so 60 miles per hour is 26.8224 meters per second. Likewise 20 mph = 8.9408 m/s.

Estimating in your head

Divide by 2.2 for a quick figure; it is off by about 1.7%. For 60 mph that gives 27.3 m/s, against 26.8224 exactly.

Going the other way

To convert meters per second to miles per hour, divide by 0.44704 (or multiply by 2.23693629205). The swap button between the boxes opens that page.

m/s = mph × 0.44704

1 mph = 0.44704 m/s and 1 m/s = 1 m/s, both by definition, so the factor is their ratio: 0.44704 exactly. Results drop binary floating-point noise beyond 15 significant digits and display at the precision you choose (6 significant figures by default). Copy result copies the full value.