Miles per hour to kilometers per hour (mph to km/h)

How do I convert miles per hour to kilometers per hour?

Multiply the number of miles per hour by 1.609344 to get kilometers per hour. For example, 25 mph × 1.609344 = 40.2336 km/h.

How many kilometers per hour are in one mile per hour?

1 mph = 1.609344 km/h and 1 km/h = 0.6213711922 mph. To go the other way, use the kilometers per hour to miles per hour converter.

How many kilometers per hour are in 80 miles per hour?

80 mph = 128.748 km/h, rounded to 6 significant digits. Change the value in the converter above for any other amount.

How many kilometers per hour are in 200 miles per hour?

200 mph = 321.869 km/h, rounded to 6 significant digits.

What is the formula for miles per hour to kilometers per hour?

km/h = mph × 1.609344, where mph is the number of miles per hour and km/h is the result in kilometers per hour. The reverse is mph = km/h × 0.6213711922.

Is the mph to km/h conversion exact?

Yes. The factor 1.609344 follows directly from the unit definitions (A mile per hour is exactly 0.44704 meters per second; a kilometer per hour is 1/3.6 of a meter per second), so the only rounding is in the digits you choose to display.

What is the difference between miles per hour and kilometers per hour?

A mile per hour is exactly 0.44704 meters per second. It is used for road speed limits and vehicle speeds in the US and UK. A kilometer per hour is 1/3.6 of a meter per second. It is used for road speed limits and vehicle speeds in most countries.