How to Convert Kilometres to Miles (km to mi)
Length conversions come up when reading overseas furniture specs, cycling the Round Island Route in kilometres while a foreign app shows miles, or checking marine distances in the Singapore Strait in nautical miles. This guide shows how to convert kilometres into miles by hand, with examples and a quick-reference table.
The conversion
To convert kilometres to miles, multiply the value by 0.6213711922. To go the other way, divide by the same number (or multiply by 1.609344). For a quick estimate, multiply by about 0.62.
Miles = kilometres × 0.6213711922
Worked examples
- 3 km = 1.8641 mi
- 12.5 km = 7.7671 mi
- 75 km = 46.6028 mi
Kilometres to Miles table
| Kilometres | Miles |
|---|---|
| 1 km | 0.621371 mi |
| 2 km | 1.2427 mi |
| 5 km | 3.1069 mi |
| 10 km | 6.2137 mi |
| 20 km | 12.4274 mi |
| 25 km | 15.5343 mi |
| 50 km | 31.0686 mi |
| 100 km | 62.1371 mi |
| 250 km | 155.3428 mi |
| 500 km | 310.6856 mi |
| 1,000 km | 621.3712 mi |
Common questions
Is km to mi exact?
The factors used here are the internationally defined values where they exist; results are rounded for display only.
How do I convert back?
Use the Miles to Kilometres converter.
Mistakes to avoid
Multiplying when you should divide
Converting to a smaller unit gives a bigger number, and converting to a larger unit gives a smaller one. If your answer moves the wrong way, you have inverted the factor.
Rounding the factor too early
Using 3 instead of 3.28 for feet per metre introduces an error of almost 9% before you have started.
Dropping the units
A bare number without a unit is easy to misread later. Always write the unit with the result.
Background
A conversion table is handy for common values, but a calculator is faster and avoids interpolation errors for anything in between.
Unit conversion is simply multiplication by a fixed ratio. The ratio between two units of the same quantity never changes, so once you know it you can convert any value in either direction.
Writing the units next to every number while you work is the simplest way to avoid mistakes. If the units do not cancel to leave the one you want, the calculation is set up wrongly.
For any value, use the Kilometres to Miles Converter or browse all length converters.
Run your own numbers: Kilometres to Miles Converter