KM to Miles Converter
Free km to miles converter — kilometres to miles with the exact factor 1 mi = 1.609344 km. Instant, two-way, running distances included.
About the KM to Miles Converter
Convert kilometres to miles using the exact factor 1 mile = 1.609344 km, so miles = km ÷ 1.609344. Enter a distance in kilometres and the miles appear instantly — 10 km is 6.21 miles — with the conversion working in both directions.
Runners and drivers hit this conversion constantly: a 5K race is 3.11 miles, a half marathon (21.0975 km) is 13.11 miles and a marathon (42.195 km) is 26.22 miles. Road-trip distances, rental-car odometers and speed limits abroad (100 km/h ≈ 62 mph) all need the same factor.
For quick mental math, multiply kilometres by 0.6 — or use the Fibonacci trick: consecutive Fibonacci numbers approximate the ratio, so 8 km ≈ 5 miles and 13 km ≈ 8 miles. The table below lists the exact values for common distances.
How to Use the KM to Miles Converter
- 1Enter a distance in kilometres — for example 10.
- 2Read the miles result instantly (10 km = 6.2137 mi).
- 3Type miles instead to convert miles back to kilometres.
- 4Check the table for 5K, 10K, half marathon and marathon distances.
Frequently Asked Questions
How many miles is 5 km?
5 km is 3.107 miles — the classic 5K race distance. A 10K is 6.214 miles and a 15K is 9.32 miles.
How many miles is a marathon in km?
A marathon is 42.195 km, which equals 26.219 miles (26 miles 385 yards). A half marathon is 21.0975 km, or 13.109 miles.
What is 100 km in miles?
100 km is 62.137 miles. This also helps with speed: 100 km/h is about 62 mph, 120 km/h is 74.6 mph and 50 km/h is 31.1 mph.
How do I convert km to miles in my head?
Multiply by 0.6 for a close estimate (10 km ≈ 6 mi; exact is 6.21). For better accuracy, take five-eighths: 16 km × 5/8 = 10 miles, which is nearly exact since 1 mi = 1.609 km.
Is the mile exactly 1.609344 km?
Yes. The international mile is 5,280 feet, and with 1 ft = 0.3048 m exactly, the mile works out to exactly 1,609.344 m. This converter uses that exact value in both directions.