MPH to KMH Converter
Convert miles per hour to kilometers per hour instantly. One mile per hour equals exactly 1.609344 kilometers per hour. Type in either box to convert both ways, then use the chart, worked examples and everyday sizes below.
Miles per hour to kilometers per hour calculator
How to convert miles per hour to kilometers per hour
Worked example: convert 90 miles per hour to kilometers per hour. Using kilometers per hour ← miles per hour × 1.609344, we get 90 × 1.609344 = 144.84096 km/h. To check the result, convert back: 144.84096 km/h ÷ 1.609344 = 90 mph.
Miles per hour to kilometers per hour chart
| Miles per hour (mph) | Kilometers per hour (km/h) |
|---|---|
| 1 mph | 1.609344 km/h |
| 2 mph | 3.218688 km/h |
| 3 mph | 4.828032 km/h |
| 4 mph | 6.437376 km/h |
| 5 mph | 8.04672 km/h |
| 6 mph | 9.656064 km/h |
| 8 mph | 12.87475 km/h |
| 10 mph | 16.09344 km/h |
| 12 mph | 19.31213 km/h |
| 15 mph | 24.14016 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 |
| 75 mph | 120.7008 km/h |
| 100 mph | 160.9344 km/h |
| 150 mph | 241.4016 km/h |
| 200 mph | 321.8688 km/h |
| 250 mph | 402.336 km/h |
| 500 mph | 804.672 km/h |
| 1,000 mph | 1,609.344 km/h |
Kilometers per hour to miles per hour (reverse)
| Kilometers per hour (km/h) | Miles per hour (mph) |
|---|---|
| 1 km/h | 0.6213712 mph |
| 2 km/h | 1.242742 mph |
| 5 km/h | 3.106856 mph |
| 10 km/h | 6.213712 mph |
| 20 km/h | 12.42742 mph |
| 50 km/h | 31.06856 mph |
| 100 km/h | 62.13712 mph |
| 250 km/h | 155.3428 mph |
| 500 km/h | 310.6856 mph |
| 1,000 km/h | 621.3712 mph |
About the mile per hour and the kilometer per hour
Miles per hour is the speed unit on road signs and speedometers in the United States and United Kingdom.
Kilometers per hour is the speed unit on road signs in most countries. A speed of 100 km/h is about 62 mph and 27.8 m/s.
One mile per hour equals 1.609344 kilometers per hour, which makes the mile per hour the faster unit of the two.
Everyday sizes in miles per hour and kilometers per hour
| Everyday example (approximate) | In miles per hour | In kilometers per hour |
|---|---|---|
| A slow walk | 3.1317 mph | 5.04 km/h |
| A jogger | 6.7108 mph | 10.8 km/h |
| A city cyclist | 12.303 mph | 19.8 km/h |
| Usain Bolt's peak sprint speed | 27.738 mph | 44.64 km/h |
| A car on a city road | 31.071 mph | 50.004 km/h |
| A car on a highway | 62.142 mph | 100.01 km/h |
Miles per hour to kilometers per hour FAQ
How many kilometers per hour are in one mile per hour?
One mile per hour equals exactly 1.609344 kilometers per hour. In the other direction, one kilometer per hour equals 0.62137119 miles per hour.
How do I convert miles per hour to kilometers per hour without a calculator?
convert 90 miles per hour to kilometers per hour. Using kilometers per hour ← miles per hour × 1.609344, we get 90 × 1.609344 = 144.84096 km/h. To check the result, convert back: 144.84096 km/h ÷ 1.609344 = 90 mph. For a quick estimate, round the factor to 1.6. Then 90 mph is about 144 km/h, compared with the exact 144.841 km/h (an error of 0.58%). That is close enough for planning, but use the calculator above when the number matters.
What is a slow walk in kilometers per hour?
A slow walk is about 3.1317 miles per hour, which is 5.04 kilometers per hour. Treat that as an approximate everyday figure rather than an official measurement.
Are the miles per hour and kilometers per hour the same in every country?
One mile per hour is exactly 0.44704 m/s. One kilometer per hour is exactly 5/18 m/s.