Kilometers to Miles Calculator
Convert a distance in kilometers (km) to miles (mi). Enter a value in kilometers and the calculator returns the distance in miles, the unit used on US roads and odometers.
How It Works
One international mile is defined as exactly 1.609344 kilometers, so to travel the other way you multiply kilometers by its reciprocal, 0.6213711922. Distance conversions are purely proportional, which means a route that is twice as long in kilometers is twice as long in miles. Runners often meet this conversion at metric race distances: a 5K, 10K, half marathon, and marathon all translate to familiar mile figures, which is why the reference table below leans on common race lengths.
Worked Examples
Example 1 — highway distance. 100 km × 0.62137 ≈ 62.14 miles.
Example 2 — 5K race. 5 km × 0.62137 ≈ 3.11 miles.
When to Use This Calculator
Use this conversion when a road sign abroad shows kilometers and you think in miles, when you want to know a metric race in mile terms, or when a fitness tracker logs distance in kilometers. It also helps when reading a European map or planning fuel stops on an overseas road trip.
| Kilometers | Miles |
|---|---|
| 1 km | 0.62 mi |
| 5 km (5K) | 3.11 mi |
| 10 km (10K) | 6.21 mi |
| 21.1 km (half) | 13.11 mi |
| 42.2 km (marathon) | 26.22 mi |
| 50 km | 31.07 mi |
| 100 km | 62.14 mi |
Frequently Asked Questions
How many miles is 1 kilometer?
One kilometer is about 0.6214 miles, so a kilometer is a little under two-thirds of a mile.
What is the quickest mental estimate?
Multiply the kilometers by 0.6 for a rough answer. For example, 10 km is roughly 6 miles, just short of the exact 6.21.
How long is a 10K in miles?
A 10-kilometer race is about 6.21 miles, which is why 10K events are sometimes described as a touch over six miles.