Convert Kilometres per hour to Miles per hour
1 kilometre per hour is 0.621371 mph. One kilometre per hour is exactly 0.621371192237 miles per hour.
One kilometre per hour is 0.62137119 miles per hour. To convert kilometres per hour to miles per hour, multiply by 0.62137119; to go the other way, divide by 0.62137119 or multiply by 1.609344. The factor is exact rather than rounded: it follows from NIST Special Publication 811. Exactly one kilometre divided by 3,600 seconds.
Factor checked against the defining standard · How we check
- Kilometres per hour × 0.62137119
value * 0.6213711922370.621 mph
1 kilometre per hour in every speed unit
| Unit | Value | Exact factor |
|---|---|---|
| metres per second | 0.2777777778 m/s | × 0.277777777778 |
| kilometres per hour (as entered) | 1 km/h | — |
| miles per hour | 0.6213711922 mph | × 0.621371192237 |
| knots | 0.5399568035 kn | × 0.539956803456 |
| feet per second | 0.9113444153 ft/s | × 0.911344415281 |
Factors are entered by hand from NIST Special Publication 811 rather than derived from a units library, so the ones that terminate are exact rather than rounded.
How do you convert kilometres per hour to miles per hour?
- 1.Take the measurement in kilometres per hour.
- 2.Multiply by 0.62137119 — that is how many miles per hour fit in one kilometre per hour.
- 3.To go back the other way, divide by 0.62137119, or multiply by 1.609344.
Kilometres per hour to miles per hour conversion table
| Kilometres per hour | Miles per hour |
|---|---|
| 1 km/h | 0.621371 mph |
| 2 km/h | 1.242742 mph |
| 3 km/h | 1.864114 mph |
| 4 km/h | 2.485485 mph |
| 5 km/h | 3.106856 mph |
| 6 km/h | 3.728227 mph |
| 7 km/h | 4.349598 mph |
| 8 km/h | 4.97097 mph |
| 9 km/h | 5.592341 mph |
| 10 km/h | 6.213712 mph |
| 12 km/h | 7.456454 mph |
| 15 km/h | 9.320568 mph |
| 20 km/h | 12.427424 mph |
| 25 km/h | 15.53428 mph |
| 50 km/h | 31.06856 mph |
| 100 km/h | 62.137119 mph |
What are kilometres per hour and miles per hour?
- Kilometre per hour (km/h)
- Exactly one kilometre divided by 3,600 seconds. The road speed unit almost everywhere outside the United States and the United Kingdom.
- Mile per hour (mph)
- Exactly 0.44704 m/s, because a mile is exactly 1,609.344 metres. US and UK road speeds.
Source: NIST Special Publication 811 — conversion factors for speed
Questions people actually ask
- How many miles per hour are in a kilometre per hour?
- 0.62137119. Exactly 0.44704 m/s, because a mile is exactly 1,609.344 metres. US and UK road speeds.
- How do I convert miles per hour back to kilometres per hour?
- Divide by 0.62137119, or multiply by 1.609344 — they are the same operation.
Other speed conversions
Miles per hour to kilometres per hour — the same conversion the other way.