Mile per Hour to Kilometer per Hour Converter
Converts mile per hour to kilometer per hour (mph to km/h) and back. The conversion factor is shown below every result.
How to Convert Mile per Hour to Kilometer per Hour
What Is a Mile per Hour?
Miles per hour (mph) measures speed using the statute mile, fixed at exactly 1,609.344 meters.
What Is a Kilometer per Hour?
The standard metric speed unit is kilometers per hour (km/h).
Common Mile per Hour to Kilometer per Hour Reference Points
Real-world reference values for quick sanity checks.
| Item | Mile per Hour (mph) | Kilometer per Hour (approx.) |
|---|---|---|
| US highway speed limit (approx.) | 65 mph | 104.61 km/h |
| A brisk walking pace | 3 mph | 4.83 km/h |
| Reference values are illustrative approximations for common items, not measured specifications. | ||
Mile per Hour to Kilometer per Hour Conversion Table
| Mile per Hour (mph) | Kilometer per Hour (km/h) |
|---|---|
| 10 mph | 16.09344 km/h |
| 20 mph | 32.18688 km/h |
| 30 mph | 48.28032 km/h |
| 40 mph | 64.37376 km/h |
| 55 mph | 88.51392 km/h |
| 65 mph | 104.60736 km/h |
| 70 mph | 112.65408 km/h |
| 80 mph | 128.74752 km/h |
| 100 mph | 160.9344 km/h |
| Source: NIST SP 811, Appendix B (1 statute mile = 1,609.344 km exactly) | |
Frequently Asked Questions
How do I convert mph to km/h?
Multiply the mph value by 1.609344. For example, 60 mph × 1.609344 = 96.56 km/h.
Is 1.609344 an exact number?
Yes. It comes directly from the definition of the statute mile as exactly 1,609.344 meters, so there's no rounding in the factor itself.
Why do US car speedometers often show both mph and km/h?
Vehicles sold across North America and other markets frequently ship with a single instrument cluster designed for multiple regions, so both scales appear even though only one is the primary legal unit in a given country.
Related Speed Converters
A good measuring tool marked in both mph and km/h removes the guesswork at the point of use.