How to convert kilometres to miles
To convert kilometres to miles, multiply by 0.6214. One kilometre is about 0.6214 miles, because a mile is defined as exactly 1.609344 km and 1 ÷ 1.609344 = 0.6214. The converter above works instantly in both directions.
A useful trick: kilometres and miles are close to the golden ratio (about 1.618), so consecutive Fibonacci numbers approximate the conversion — 5 km ≈ 3 miles, 8 km ≈ 5 miles, 13 km ≈ 8 miles. It is surprisingly accurate for quick mental maths.
Where you’ll use kilometres to miles
Most countries measure road distances and speed in kilometres, while the US and UK use miles. Converting km to miles comes up for:
- Driving abroad: reading road signs, odometers and sat-nav distances in a metric country and thinking in miles.
- Running and cycling: race distances such as 5K, 10K and half-marathons are set in kilometres, but many runners track pace in miles.
- Speed limits: a 100 or 130 km/h motorway limit converted to mph (the factor is the same for speed).
- Travel planning: estimating how long a trip quoted in kilometres will feel in miles.
- Fitness apps: switching a workout logged in one unit to the other.
Kilometres and miles: what each unit is
The kilometre is a metric unit equal to 1,000 metres. The mile (statute mile) is an imperial and US customary unit equal to 5,280 feet, or exactly 1.609344 kilometres. Because the mile is legally defined against the metre, the conversion is exact — only the displayed decimals are rounded.
Kilometres to Miles conversion table
| Kilometres | Miles |
|---|
Popular running distances in km and miles
| Race | Kilometres | Miles |
|---|---|---|
| 5K | 5 km | 3.11 mi |
| 10K | 10 km | 6.21 mi |
| Half marathon | 21.1 km | 13.11 mi |
| Marathon | 42.195 km | 26.22 mi |
| Motorway limit | 100 km/h | 62.1 mph |
| Motorway limit | 130 km/h | 80.8 mph |
Worked examples
Convert 5 km to miles
5 × 0.6214 = 3.11 miles — a popular race distance.
Convert 100 km/h to mph
Using the same factor, 100 km/h × 0.6214 = 62.1 mph.
Convert a 42.195 km marathon to miles
42.195 × 0.6214 = 26.22 miles, the classic marathon distance.
Frequently asked questions
One kilometre is about 0.6214 miles.
A marathon is 42.195 km, which is 26.219 miles.
Yes. km/h to mph uses the same 0.6214 factor, because it is the same length ratio per hour.
A mile is longer. One mile is about 1.61 km, so a mile is roughly 61% longer than a kilometre.