Convert Miles per hour to Kilometers per hour
One mile per hour equals 1.609344 kilometers per hour. Type any value to convert miles per hour to kilometers per hour instantly — with a full reference table below.
Convert Miles per hour to Kilometers per hour
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How to convert Miles per hour to Kilometers per hour
To convert miles per hour to kilometers per hour, multiply by 1.609344. One mile per hour equals 1.609344 km/h, and one kilometer per hour equals 0.621371 mph.
- Take the value in miles per hour — for example 7.5 mph.
- Multiply by 1.609344 (the number of kilometers per hour in one mile per hour).
- 7.5 × 1.609344 = 12.07008 km/h.
Quick mental estimate: Multiply the number of miles per hour by 1.6 (within 0.6% of the exact answer).
Miles per hour to Kilometers per hour conversion table
| Miles per hour | Kilometers per hour |
|---|---|
| 1 mph | 1.609344 km/h |
| 5 mph | 8.04672 km/h |
| 10 mph | 16.09344 km/h |
| 20 mph | 32.18688 km/h |
| 25 mph | 40.2336 km/h |
| 30 mph | 48.28032 km/h |
| 40 mph | 64.37376 km/h |
| 50 mph | 80.4672 km/h |
| 60 mph | 96.56064 km/h |
| 70 mph | 112.6541 km/h |
| 80 mph | 128.7475 km/h |
| 100 mph | 160.9344 km/h |
| 120 mph | 193.1213 km/h |
| Kilometers per hour | Miles per hour |
|---|---|
| 1 km/h | 0.621371 mph |
| 5 km/h | 3.106856 mph |
| 10 km/h | 6.213712 mph |
| 20 km/h | 12.42742 mph |
| 25 km/h | 15.53428 mph |
| 30 km/h | 18.64114 mph |
| 40 km/h | 24.85485 mph |
| 50 km/h | 31.06856 mph |
| 60 km/h | 37.28227 mph |
| 70 km/h | 43.49598 mph |
| 80 km/h | 49.7097 mph |
| 100 km/h | 62.13712 mph |
| 120 km/h | 74.56454 mph |
About converting Miles per hour to Kilometers per hour
Miles per hour (mph) and Kilometers per hour (km/h) are both units of speed. The exact factor is 1 mph = 1.609344 km/h, so multiply by 1.609344 to go from miles per hour to kilometers per hour (or divide to go back).
The conversion runs entirely in your browser. Need the reverse? Use the Kilometers per hour to Miles per hour converter, or the full unit converter for every unit at once.
Real-world speed in miles per hour and kilometers per hour
| Example | Miles per hour | Kilometers per hour |
|---|---|---|
| A walking pace | ≈ 3.131711 mph | ≈ 5.04 km/h |
| Usain Bolt's top speed (2009) | ≈ 27.78275 mph | ≈ 44.712 km/h |
| The UK motorway limit (70 mph) | 70 mph | 112.6541 km/h |
| The German Autobahn advisory speed (130 km/h) | 80.77823 mph | 130 km/h |
| The speed of sound (air, 20 °C) | ≈ 767.2691 mph | ≈ 1,234.8 km/h |
| An airliner at cruise | ≈ 559.2341 mph | ≈ 900 km/h |
“≈” marks typical values; the rest are defined or measured figures.
The units
Miles per hour — exactly 0.44704 m/s.
Used for: Road speeds in the US and UK.
Kilometres per hour — exactly 1/3.6 m/s.
Used for: Road speeds in most countries.
km/h, mph, ft/s and knots are all defined exactly in metres per second (a knot is one nautical mile, exactly 1,852 m, per hour).