Length and Area
kmtomi
Convert kilometres (km) to miles (mi).
Factor1 km = 0.6213712 mi
Converter
km
Accepts numbers or expressions, e.g. 150 + 14.7
Result
mi
Rendered to 6 significant figures.
Formula
Formula
mi = km × 0.6213712
Multiply any value in kilometres by 0.6213712 to obtain the value in miles.
Worked example
Convert 100 km to mi.
- 01Start with 100 km.
- 02Multiply by the conversion factor: 100 × 0.6213712 = 62.1371 mi.
Result100 km = 62.1371 mi
Conversion table
| km | mi |
|---|---|
| 1 | 0.62137 |
| 2 | 1.2427 |
| 5 | 3.1069 |
| 10 | 6.2137 |
| 20 | 12.427 |
| 50 | 31.069 |
| 100 | 62.137 |
| 200 | 124.27 |
| 500 | 310.69 |
| 1000 | 621.37 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from km to mi?
1 km equals 0.6213712 mi. To convert, multiply the value in kilometres by 0.6213712.
How do I convert 1 km to mi?
1 km = 0.621371 mi. For any value, multiply by 0.6213712.
How do I convert mi back to km?
Divide by the same factor — or equivalently, multiply by 1.609344. So 1 mi = 1.60934 km.
When would I need to convert kilometre to mile?
Length conversions appear in piping, layout, and mechanical drawings — particularly when reconciling imperial fittings or instrument lengths with metric plant drawings.
Is the conversion exact?
Yes. Both km and mi are defined by exact SI relationships, so the displayed factor is exact (any rounding shown is only for display).