Miles per hour is a unit of speed, expressing the number of international miles covered per hour. The common abbreviation in everyday use is mph, although mi/h, using the SI method of expressing derived units, is sometimes used, especially in the United States. The preferred SI unit for velocity is m/s, although km/h is often used as a replacement for mph.

1 mph is equal to:

• 0.44704 m/s, the SI derived unit
• 1.609344 km/h
• 22/15 =1.4667 feet per second
• approx. 0.868976 knots

Miles per hour is the unit used for speed limits on roads in the US and Britain. Here are some typical limits and their approximate equivalent in km per hour.

• 20 mph — home zones and residential areas in towns = 30 km/h
• 30 mph — normal speed limit in built up areas in the UK = 50 km/h
• 55 mph — speed limit on some US freeways = 90 km/h
• 70 mph — speed limit on UK motorways = 110 km/h

External links

• Conversion Calculator for Units of SPEED