How to convert miles per hour to kilometers per hour
To convert a measurement in miles per hour to kilometers per hour, multiply the value by 1.609344. The conversion factor comes from the relationship between both units and the meter per second.
For example, to convert 5 mph to kilometers per hour: 5 × 1.609344 = 8.04672 km/h.
What is a mile per hour?
The mile per hour is an imperial unit of speed equal to one mile traveled in one hour, or exactly 0.44704 meters per second. Mph remains the standard for road speed in the United States and United Kingdom, a legacy of the imperial mile that predates widespread metric adoption elsewhere.
Common uses of miles per hour include: Road speed limits in the US and UK; Vehicle speedometers in imperial countries; Wind and storm speed reporting (US); Baseball pitch and sports speeds.
What is a kilometer per hour?
The kilometer per hour is a metric unit of speed equal to one kilometer traveled in one hour, or exactly 1/3.6 meters per second. Km/h became the standard for road speed limits in most of the world as motor vehicles spread in the 20th century, pairing naturally with the metric system's kilometer.
Common uses of kilometers per hour include: Road speed limits in most countries; Vehicle speedometers worldwide; Weather reports for wind speed; Cycling and running pace tracking.
When you need to convert miles per hour to kilometers per hour
Visitors to metric countries, sports fans, and weather watchers convert mph to km/h to interpret speeds in local terms. A 95 mph fastball or a 65 mph limit becomes meaningful once expressed in km/h.
Miles per hour to kilometers per hour worked examples
Here are some common values converted:
1 mph = 1.609344 km/h 5 mph = 8.04672 km/h 10 mph = 16.09344 km/h 50 mph = 80.4672 km/h 100 mph = 160.9344 km/h
Frequently asked questions
How many kilometers per hour are in one mile per hour?
One mile per hour (mph) equals 1.609344 kilometers per hour (km/h). Multiply any value in miles per hour by 1.609344 to convert to kilometers per hour.
How do I convert miles per hour to kilometers per hour?
Multiply the value in miles per hour by 1.609344. For example, 5 mph × 1.609344 = 8.04672 km/h.
How do I convert kilometers per hour to miles per hour?
Multiply the value in kilometers per hour by 0.621371192237, or divide by 1.609344. Use the swap button on the converter above to reverse the direction.
Is the mile per hour to kilometer per hour conversion exact?
Conversions between m/s, km/h, mph, knots and ft/s are exact by definition. Mach uses the speed of sound at sea level and 15°C (340.29 m/s), which varies with temperature and altitude.
What is the formula for miles per hour to kilometers per hour?
The formula is: km/h = mph × 1.609344. This comes from the definition of both units relative to the meter per second.