MPH to KM/H Converter
Enter a speed in miles per hour to see it in kilometers per hour right away. Edit either box and the other updates live. The math runs in your browser.
How to convert mph to km/h
- Type the speed in miles per hour into the left box.
- Read the kilometers per hour value in the right box as it updates live.
- Edit the km/h box instead to convert back to mph.
Examples
US freeway speed
60 mph
96.56 km/h
Highway speed limit
70 mph
112.65 km/h
Frequently asked questions
What is the formula to convert mph to km/h?
Multiply the speed in miles per hour by 1.609344. So km/h = mph times 1.609344. For example, 60 mph becomes 60 times 1.609344, which is about 96.56 km/h.
How do common US speed limits convert to km/h?
A 30 mph urban limit is about 48 km/h, 55 mph is about 89 km/h, 65 mph is about 105 km/h, and a 70 mph highway limit is about 113 km/h.
What are some common mph to km/h conversions?
10 mph is about 16.09 km/h, 25 mph is about 40.23 km/h, 50 mph is about 80.47 km/h, and 100 mph is about 160.93 km/h.
Why is 1 mph equal to 1.609344 km/h?
A mile is defined as exactly 1609.344 meters, or 1.609344 kilometers. Since both speeds use the same hour, one mile per hour equals 1.609344 km/h.
Is this conversion exact?
Yes. The factor 1.609344 is exact by definition, so 60 mph is exactly 96.56064 km/h. Results are rounded for display, but the calculation is precise.
Is my data sent anywhere?
No. The conversion runs entirely in your browser, so the speeds you enter never leave your device.
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