Miles Per Hour to Kilometers Per Hour
Miles per hour is the standard speed unit on road signs and speedometers in the US and UK. Kilometers per hour is the standard speed unit on road signs and speedometers outside the US and UK. 1 mph equals ≈1.60934 km/h, so converting between them is a matter of multiplying by that fixed factor — type any value into the converter below and both sides update instantly as you type.
Both units belong to speed, measured here against speed's base unit (m/s) — every other speed unit on this site converts through that same reference point, which is why the table below can also be read as a quick cross-check against nearby values.
Formula
km/h = mph × ≈1.60934
mph = km/h × ≈0.621371
Worked example: 5 mph × ≈1.60934 = 8.04672 km/h.
Conversion table
| Mile per hour (mph) | Kilometer per hour (km/h) |
|---|---|
| 1 mph | ≈1.60934 km/h |
| 2 mph | ≈3.21869 km/h |
| 3 mph | ≈4.82803 km/h |
| 5 mph | 8.04672 km/h |
| 10 mph | ≈16.0934 km/h |
| 20 mph | ≈32.1869 km/h |
| 25 mph | 40.2336 km/h |
| 50 mph | 80.4672 km/h |
| 100 mph | ≈160.934 km/h |
| 250 mph | 402.336 km/h |
| 500 mph | 804.672 km/h |
| 1,000 mph | ≈1,609.34 km/h |
Frequently asked
- How many Kilometers per hour in a mile per hour?
- 1 mph equals ≈1.60934 km/h.
- How do I convert Miles per hour to Kilometers per hour?
- Multiply the value in mph by ≈1.60934 to get km/h. The converter above does this instantly as you type.
- Is the conversion exact?
- Yes — Mile per hour and Kilometer per hour are both defined by a fixed conversion factor to speed's base unit (m/s), so the result shown is exact to the precision displayed, not an approximation.