Kilometers to Miles Converter
Convert kilometers to miles instantly and back. Uses the exact 0.621371 miles per km factor, with worked examples, a running and driving chart and common km to mi conversions.
Updated 2026-06-14 · Free · No sign-up · Runs privately in your browser
Show the formula & steps
How the Kilometers to Miles Converter Works
This converter switches between kilometers (km) and miles (mi) in both directions, using the exact factor of 1.609344 km per mile. Type a value, pick the direction, and the answer updates live with the steps shown.
The Formula
Miles = kilometers ÷ 1.609344 (equivalently, miles ≈ kilometers × 0.621371)
The mile here is the international statute mile used for road distance. To convert miles back to kilometers, multiply by 1.609344 instead.
Worked Example
Convert 10 kilometers to miles:
- 10 ÷ 1.609344 = 6.21 miles
Convert 42.195 kilometers (a marathon) to miles:
- 42.195 ÷ 1.609344 = 26.22 miles
Running and Driving Chart
| Kilometers | Miles |
|---|---|
| 1 | 0.62 |
| 5 | 3.11 |
| 10 | 6.21 |
| 21.1 (half) | 13.11 |
| 42.195 (marathon) | 26.22 |
The Quick Mental Shortcut
For a fast estimate, multiply kilometers by 0.6 to get miles, or multiply miles by 1.6 to get kilometers. This is accurate to within about 3%. For race distances, navigation and engineering, use the exact 0.621371 factor.
Frequently asked questions
How many miles are in a kilometer?+
One kilometer equals about 0.621371 miles, just under two-thirds of a mile. So 1 mile is exactly 1.609344 km.
How do I convert kilometers to miles?+
Multiply the number of kilometers by 0.621371 (or divide by 1.609344). For example, 10 km × 0.621371 = 6.21 miles.
How many miles is 10 km?+
10 kilometers equals about 6.21 miles. Divide 10 by 1.609344 to get the precise value of 6.214 miles.
What is the quick mental shortcut for km to miles?+
Multiply kilometers by 0.6, or take about two-thirds. For example, 10 km ≈ 6 miles. For miles to km, multiply by 1.6.
How many miles is 100 km?+
100 kilometers equals about 62.14 miles. Divide 100 by 1.609344 to confirm the figure of 62.137 miles.