Converters · Free tool
Miles to Kilometres Converter
Type a distance in miles to get kilometres, or in kilometres to get miles. One mile is exactly 1.609344 km, so a marathon’s 26.2 miles works out to the official 42.195 km.
The conversion, exactly
To convert miles to kilometres, multiply by 1.609344. To convert kilometres to miles, divide by the same number (or multiply by 0.621371). So 5 miles is 8.05 km, and 10 km is 6.21 miles.
Race distances are defined in metric: the half marathon is 21.0975 km and the marathon 42.195 km. The familiar “13.1” and “26.2” are those metric distances rounded to miles, which is why the mile figures look slightly imprecise.
Frequently asked questions
How many km is a marathon?
A marathon is 42.195 km, which is 26.219 miles — usually rounded to 26.2. A half marathon is 21.0975 km, or 13.1 miles.
Is a 5K the same as 5 miles?
No. A 5K is 5 kilometres, which is 3.11 miles. Five miles is 8.05 km — noticeably further.