How many kilometers per hour are in a mile per hour?

1 mph = 1.6093 km/h. To convert any amount, multiply by 1.6093.

How do you convert miles per hour to kilometers per hour?

Multiply the number of miles per hour by 1.6093 to get kilometers per hour. The formula is shown in the "How it's calculated" section above.

Where does the conversion factor come from?

It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.

Unit converter — Velocity

Miles per hour to kilometers per hour converter

Convert miles per hour (mph) to kilometers per hour (km/h). Source-cited conversion factor, exact to the displayed precision.

Results are mathematically exact for the displayed precision. How we calculate.

How it's calculated

Convert miles per hour to kilometers per hour— the formula

Miles per hour convert to kilometers per hour by multiplying by the published conversion factor. The factor below is exact to the precision shown, sourced from the citation under the formula.

km/h = mph × 1.6093

mph = km/h × 0.621371

m/s: SI derived (m × s⁻¹). 1 km/h = 1000/3600 m/s; 1 mph = 0.44704 m/s exactly; 1 knot = 1852/3600 m/s exactly (international nautical mile).

Questions

Frequently asked questions

How many kilometers per hour are in a mile per hour?
1 mph = 1.6093 km/h. To convert any amount, multiply by 1.6093.
How do you convert miles per hour to kilometers per hour?
Multiply the number of miles per hour by 1.6093 to get kilometers per hour. The formula is shown in the "How it's calculated" section above.
Where does the conversion factor come from?
It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.