How to convert miles to kilometers
Multiply the number of miles by 1.609344. The mile has been exactly 1,609.344 meters since the 1959 agreement that fixed the yard at 0.9144 m: a mile is 1,760 yards, 1,760 × 0.9144 = 1,609.344.
Worked example: a car's trip meter shows 62 miles. 62 × 1.609344 = 99.7793 km. A 26.2 mile marathon distance as printed on a US race page is 42.165 km, a little under the official 42.195.
Because 1.609344 has six decimals, a whole number of miles gives an exact answer, and a mile figure with two decimals gives an answer with at most eight.
Miles on the road
The UK and the US still sign roads in miles. Drivers who cross into a country that uses kilometers need to think about speed and distance in both:
- 20 mph is 32.2 km/h.
- 30 mph is 48.3 km/h.
- 40 mph is 64.4 km/h.
- 50 mph is 80.5 km/h.
- 60 mph is 96.6 km/h.
- 70 mph is 112.7 km/h.
For fuel and trips, 100 miles is 160.934 km. For the reverse direction use km to miles.
Not every mile is the same
- Statute mile: 1,609.344 m, the land mile of roads and running tracks. This page uses it.
- Nautical mile: exactly 1,852 m, about 1.151 statute miles. Used at sea and in the air, so a speed in knots is nautical miles per hour.
- US survey mile: based on the survey foot, 5,280 survey feet. About 3 mm longer than the statute mile and retired along with the survey foot. It is not listed separately here.
- Old miles: the Roman, Scots and Irish miles all differed. They show up in historical texts but not in measurements today.
If a source does not say which mile it means, it is the statute mile. For more units use the length converter.