To convert miles to kilometers, multiply by 1.609344. One mile is exactly 1.609344 km, so 10 miles is 16.09 km and a 26.2-mile marathon is 42.16 km.
The US and UK sign roads in miles; nearly everywhere else uses kilometers. Runners also switch between them constantly, because race distances are metric but many training logs are in miles.
How to use the miles to km converter
- Type the value in miles into the box. Decimals are fine.
- The result in kilometers updates as you type, along with the working.
- Need the other way? Switch the direction menu, or open the km to miles converter.
Formula
A statute mile is 5,280 ft, and because the foot is exactly 0.3048 m, a mile is exactly 1,609.344 m, or 1.609344 km. A nautical mile (1.852 km) is a different unit used at sea and in aviation.
Worked example
How far is a 26.2-mile marathon in km?
- 26.2 × 1.609344 = 42.1648.
- Result: 42.16 km.
The official marathon is 42.195 km, which is 26 miles 385 yards (26.219 mi). "26.2" is a rounded figure, so converting it gives a slightly short answer.
Miles to kilometers chart
Common values, rounded to 4 decimal places.
| Miles (mi) | Kilometers (km) |
|---|---|
| 1 mi | 1.6093 km |
| 2 mi | 3.2187 km |
| 3 mi | 4.828 km |
| 5 mi | 8.0467 km |
| 10 mi | 16.0934 km |
| 13.1 mi | 21.0824 km |
| 15 mi | 24.1402 km |
| 20 mi | 32.1869 km |
| 25 mi | 40.2336 km |
| 26.2 mi | 42.1648 km |
| 50 mi | 80.4672 km |
| 60 mi | 96.5606 km |
| 100 mi | 160.9344 km |
| 250 mi | 402.336 km |
| 500 mi | 804.672 km |
| 1,000 mi | 1,609.344 km |
Where miles are used
- Roads: US and UK distance signs, odometers and speed limits (see mph to km/h converter).
- Running: US training plans list miles; a half marathon is 13.1 mi (21.0975 km).
- Flights: airline mileage programs count statute miles, while pilots use nautical miles.
Quick mental math
Multiply by 1.6. For a neat trick, use consecutive Fibonacci numbers: 3 mi ≈ 5 km, 5 mi ≈ 8 km, 8 mi ≈ 13 km, 13 mi ≈ 21 km.
Related conversions
Going the other way: km to miles converter. Related pages: inches to cm converter, cm to inches converter, feet to meters converter. For other units in the same family, use the full length converter or the pace calculator.
Caveats and assumptions
- Results show up to 10 significant digits; the chart is rounded for reading. Keep full precision for engineering, medical or legal work.
Frequently asked questions
How many kilometers are in a mile?
Exactly 1.609344 km.
What is 10 miles in km?
16.09344 km.
Is a nautical mile the same as a mile?
No. A nautical mile is 1.852 km (about 1.15 statute miles).
How many km is a half marathon?
21.0975 km, which is 13.1094 miles.
Sources
- NIST — SI Units: Length (1959 definition of the inch) — 1 in = 25.4 mm exactly
- NIST SP 811 Appendix B.9 — Conversion factors — mile (international) to meter
This calculator gives estimates for planning and education. Check measurements, local codes, supplier specs and your school's official policy before relying on a result. See our disclaimer and how we build and check calculators.