mile per hour to kilometer per hour
Convert mile per hour (mph) to kilometer per hour (km/h). Use an editable speed converter, conversion formula, and reference table.
1 mph = 1.609344 km/h
Conversion formula
One mile per hour equals 1.609344 kilometer per hour. Multiply your value in mile per hour by this factor to get kilometer per hour. For the reverse conversion, divide by the same factor.
Worked example
To convert 5 mile per hour:5 × 1.609344 = 8.04672 km/h
Conversion table
| mile per hour (mph) | kilometer per hour (km/h) |
|---|---|
| 0.01 | 0.01609344 |
| 0.1 | 0.1609344 |
| 1 | 1.609344 |
| 2 | 3.218688 |
| 5 | 8.04672 |
| 10 | 16.09344 |
| 25 | 40.2336 |
| 50 | 80.4672 |
| 100 | 160.9344 |
| 1000 | 1,609.344 |
About these measurements
Speed is distance traveled per unit of time.
The base reference used here is the meter per second. One mile per hour is 0.44704 base units; one kilometer per hour is 0.2777777778 base units.
Important distinctions
Mach is excluded because the speed of sound depends on medium and temperature.
Precision
The converter uses stored conversion factors and floating-point arithmetic. Results display up to ten significant digits, switching to scientific notation for very small or large values. Keep the precision of your original measurement when reporting results.
Common questions
How do I convert mph to km/h?
Multiply the quantity in mph by 1.609344. You can also type the value into the converter above.
Can I reverse the conversion?
Yes. Use the swap button or open the kilometer per hour to mile per hour converter.
Reference
NIST Guide to the SI — conversion factors and prefix conventions. SI prefixes scale units by powers of ten; the dimension-specific notes above describe the assumptions used on this page.
