The short answer
- 1 mph = 1.609344 km/h
- 1 km/h ≈ 0.6213712 mph
Worked example70 mph × 1.609344 = 112.6541 km/h
UNIT CONVERSION
← Speed converterMiles per hour to kilometres per hour
To convert miles per hour to kilometres per hour, multiply the number of miles per hour by 1.609344.
What the units mean
Mile per hour. Miles per hour. The international mile is exactly 1,609.344 metres, so 1 mph is exactly 0.44704 metres per second.
Kilometre per hour. Kilometres per hour. 1 km/h is exactly 1/3.6 metres per second.
Miles per hour to kilometres per hour table
| Miles per hour (mph) | Kilometres per hour (km/h) |
|---|---|
| 5 | 8.04672 |
| 10 | 16.09344 |
| 15 | 24.14016 |
| 20 | 32.18688 |
| 25 | 40.2336 |
| 30 | 48.28032 |
| 35 | 56.32704 |
| 40 | 64.37376 |
| 45 | 72.42048 |
| 50 | 80.4672 |
| 55 | 88.51392 |
| 60 | 96.56064 |
| 65 | 104.6074 |
| 70 | 112.6541 |
| 75 | 120.7008 |
| 80 | 128.7475 |
| 90 | 144.841 |
| 100 | 160.9344 |
| 120 | 193.1213 |
| 150 | 241.4016 |
| 200 | 321.8688 |
Values are rounded to 7 significant figures.
Common questions
How do I convert miles per hour to kilometres per hour?
Multiply the number of miles per hour by 1.609344. For example, 70 mph × 1.609344 = 112.6541 km/h.
How many kilometres per hour are in one mile per hour?
One mile per hour is exactly 1.609344 kilometres per hour.
Is this conversion exact?
Yes. Both units have exact legal definitions, so the factor is exact. Values on this page are rounded to 7 significant figures.