How to convert miles per hour to kilometres per hour
Enter a speed in miles per hour and read it in kilometres per hour. The result updates as you type, and you can swap the units or copy the answer.
One mile per hour is exactly 1.609344 km/h, because the mile is defined as 1.609344 km.
1 mile per hour = 1.609344 kilometres per hour
Formula: kilometres per hour = miles per hour × 1.609344
- Multiply the speed in mph by 1.609344.
- For a quick estimate, multiply by 1.6. For 60 mph that gives 96 km/h, against an exact 60 mph = 96.56 km/h.
Common conversions
| Miles per hour (mph) | Kilometres per hour (km/h) |
|---|---|
| 5 mph | 8.04672 km/h |
| 10 mph | 16.0934 km/h |
| 20 mph | 32.1869 km/h |
| 30 mph | 48.2803 km/h |
| 40 mph | 64.3738 km/h |
| 50 mph | 80.4672 km/h |
| 60 mph | 96.5606 km/h |
| 70 mph | 112.654 km/h |
| 80 mph | 128.748 km/h |
| 100 mph | 160.934 km/h |
Values are computed by the same converter as above, rounded to six significant digits. Need the other direction? See Kilometres per Hour to Miles per Hour.
Worked examples
A UK single carriageway
The national speed limit on UK single carriageways is 60 mph: 60 mph = 96.6 km/h.
A UK motorway
The UK motorway limit of 70 mph is 70 mph = 112.7 km/h.
A US interstate
A 65 mph limit on a US interstate is 65 mph = 104.6 km/h.
A residential street
30 mph is 30 mph = 48.3 km/h.
Things to keep in mind
- The UK and the US post speed limits in miles per hour. Most other countries use kilometres per hour, so a hire car abroad may show either or both.
- km/h, kph and kmph are three ways of writing the same unit.