Convert Miles to Kilometers
Miles to kilometers is the conversion you reach for when a distance is written in the imperial system but you think — or drive, or run — in metric. One mile is exactly 1.609344 kilometers, so the number always gets bigger when you switch from miles to km.
Miles to Kilometers conversion table
| Miles (mi) | Kilometers (km) |
|---|---|
| 1 | 1.609344 |
| 2 | 3.218688 |
| 3 | 4.828032 |
| 5 | 8.04672 |
| 10 | 16.09344 |
| 20 | 32.18688 |
| 50 | 80.4672 |
| 100 | 160.9344 |
| 500 | 804.672 |
| 1,000 | 1,609.344 |
The formula
To convert miles to kilometers, multiply the distance in miles by 1.609344:
kilometers = miles × 1.609344
A worked example
Say you want to convert a 26.2-mile marathon into kilometers:
26.2 × 1.609344 = 42.16 km
That is why a marathon is often quoted as 42.195 km — the official course length is defined in metric and works out to just over 26.2 miles.
Why the number is exact
The mile and the kilometer come from two different systems, but they are tied together precisely: one international mile is defined as 1609.344 metres exactly. That makes every miles-to-kilometers conversion exact rather than an approximation, which matters for engineering, mapping, and anything where small errors add up over long distances.
When you'll use it
Reading road signs or race distances abroad, comparing car odometers, converting running or cycling logs, and working with maps that mix imperial and metric units.
Frequently asked questions
How many kilometers are in a mile?
Exactly 1.609344 kilometers. The value is exact by international agreement, not a rounded approximation, because the mile is officially defined in terms of the metre.
Is the mile to kilometer conversion exact?
Yes. Since 1959 the international mile has been defined as exactly 1609.344 metres, so multiplying by 1.609344 is precise — any rounding you see is only in how the result is displayed.
What's a quick way to estimate miles to kilometers in my head?
Add roughly 60%. A 10-mile drive is about 16 km; a 5-mile run is about 8 km. For anything that matters, use the exact factor above.