How to convert kilometers to miles
Divide the number of kilometers by 1.609344, or multiply by 0.621371192. A mile is exactly 1,609.344 meters (5,280 feet of 0.3048 m each), so 1 km is a little over six tenths of a mile.
Worked example: a road sign says 80 km to the next town. 80 ÷ 1.609344 = 49.71 miles. A speed limit of 100 km/h is 62.14 mph, and 130 km/h is 80.8 mph.
Running distances in kilometers and miles
Races are measured in kilometers almost everywhere, but runners in the US and UK often track miles:
- 5K is 3.107 miles.
- 10K is 6.214 miles.
- Half marathon is 21.0975 km, which is 13.109 miles.
- Marathon is 42.195 km, which is 26.219 miles, usually given as 26 miles and 385 yards.
- 50K ultra is 31.07 miles, and 100K is 62.14 miles.
To compare paces, remember that a pace in minutes per mile is about 1.6 times a pace in minutes per kilometer.
A shortcut that gets within one percent
The ratio between miles and kilometers is close to the ratio of two numbers from the Fibonacci sequence, 5 to 8. That gives a mental trick: 5 miles is about 8 km, and so 8 km is about 5 miles.
For other distances, multiply by 0.6 and then add about 3.5 percent of the result. 50 km × 0.6 = 30, plus 1 is 31, against the exact 31.07 miles. For anything where the last digit matters, use the converter above.