The miles to km conversion factor
One mile equals 1.60934 kilometers, so to convert miles to kilometers you multiply by 1.60934: km = miles × 1.60934. For example, a marathon of 26.2 miles × 1.60934 = 42.16 km. To reverse it, use the km to miles calculator.
The factor is exact by definition, because a mile is 1,609.344 metres once the international yard is fixed at 0.9144 m. For a mental estimate, add six tenths: 10 miles is roughly 16 km and 50 miles roughly 80 km, which is within one per cent of the true value.
Many people follow this up with the steps to miles calculator.
How to convert miles to kilometers
Enter a distance in miles and the calculator multiplies by 1.60934 to return kilometers. Useful for running, driving, and travel. Round to two decimal places for everyday use.
Worked examples for runners: a 5K is 3.11 miles, a 10K is 6.21 miles, a half marathon of 13.1 miles is 21.08 km, and the full 26.2 miles is 42.16 km.
Race distances are set in kilometres and only described in miles, so the metric figure is the official one. A 5K is exactly 5,000 m however the mile equivalent is rounded.
The mph to km/h calculator is the natural next step once you have this figure.
Miles to km reference table
| Miles | Kilometers |
|---|---|
| 1 mi | 1.61 km |
| 5 mi | 8.05 km |
| 10 mi | 16.09 km |
| 26.2 mi | 42.16 km |
Speeds convert with the same factor: 30 mph is 48.3 km/h, 60 mph is 96.6 km/h and 70 mph is 112.7 km/h. That is why continental limits of 50, 100 and 120 km/h feel familiar to a driver used to miles without ever matching exactly.
The meters to kilometers calculator answers the question that usually follows this one.
Frequently asked questions
- How many km is 26.2 miles?
- 26.2 miles equals 42.16 km (26.2 × 1.60934).
- What is the miles to km formula?
- kilometers = miles × 1.60934, since 1 mile is 1.60934 km.
- How many miles are in a kilometer?
- One kilometer is about 0.621 miles.
- How do I convert km back to miles?
- Divide kilometers by 1.60934, or use the km to miles calculator.
- Is a nautical mile the same as the mile used here?
- No. A nautical mile is 1.852 km, about 15% longer than the statute mile of 1.60934 km that this calculator uses. Shipping and aviation distances are in nautical miles, so check which one your source means.