miles per hour to kilometers per hour Converter
Type a value in miles per hour and get the answer in kilometers per hour instantly — or convert the other way. The conversion uses the exact relationship 1 miles per hour = 1.60934 kilometers per hour, the same formula used in textbooks and engineering references.
Driving from the US or UK into a km/h country? The numbers on the dashboard and the signs suddenly disagree. One mph is exactly 1.609344 km/h — multiply by 1.6 for a road-safe estimate.
How to use
- Type your value into the miles per hour box — the kilometers per hour result updates as you type.
- To go the other direction, type into the kilometers per hour box instead and read the miles per hour result.
- Copy the result with one tap, or scan the reference table below for common values.
Frequently asked questions
How do you convert miles per hour to kilometers per hour?
Multiply the number of miles per hour by 1.60934. For example, 10 miles per hour = 16.0934 kilometers per hour. The converter above does this for you and shows more decimal places than you will ever need.
How many kilometers per hour are in one miles per hour?
Exactly 1.60934 kilometers per hour. This is a fixed definition, not an approximation, so the conversion is exact at any scale.
Is this converter accurate for professional use?
Yes — it uses full double-precision arithmetic and the official miles per hour-to-kilometers per hour factor, so results are reliable for schoolwork, cooking, fitness, travel and technical work.
Can I convert kilometers per hour back to miles per hour?
Yes. The converter is two-way: just type in the second box and the first box updates instantly with the reverse conversion.