Converters guide
Miles to kilometers for road signs and race calendars
US road trips and many race calendars still think in miles. World Athletics and most road signs outside the US think in kilometers. The statute mile is 1.609344 km exactly — 5,280 international feet.
Updated 2026-09-19
Races people actually type
A 5K is 3.107 miles, not “about 3.” A 10K is 6.214 miles. A half marathon (13.109 miles) is 21.0975 km. A marathon is 26.219 miles / 42.195 km. Convert the distance on the bib, then set the watch to the unit you trained in.
26.2 miles is a rounding of 26.21875. If you pace a 26.2 file on a 42.195 km course you will be slightly short in your head and fine on the road.
Not a nautical mile
A nautical mile is 1.852 km. Aviation and marine GPS use that. Do not run a statute-mile converter on a nmi waypoint.
Key takeaways
- miles × 1.609344 = km.
- 5K / 10K / marathon distances are fixed; convert those, do not invent them.
- Nautical miles are a different page.