Mph to Km/h

Visitors from metric countries usually need this direction. Common US limits of 25, 55, 65 and 70 mph are 40.2, 88.5, 104.6 and 112.7 km/h. The UK motorway limit is also 70 mph, the same 112.7 km/h.

Rural interstate limits of 70 to 75 mph, common in many states, are 113 to 121 km/h.

The mile is defined as 5,280 international feet of 0.3048 m, which works out to exactly 1,609.344 m. An hour is the same in both units, so mph to km/h is just miles to kilometers. The definitions are in NIST Handbook 44.

For distance instead of speed, see km to miles, and for the reverse of this page, km/h to mph.

The UK is one of the few countries besides the US that still post road speeds in mph, so drivers coming over from France switch units at the border. Speed cameras and car manuals follow the local unit, and many modern cars let you change the main speed display in the settings menu.

Electric scooters and bikes follow the same split. A US e-bike limited to 20 mph rides at about 32 km/h, while European e-bikes are commonly limited to 25 km/h, about 15.5 mph. Wind speeds on US forecasts are also given in mph, and the same factor turns them into km/h for comparison with metric reports.