Kilometers to Miles: Conversion Chart, Formula & Calculator
Convert kilometers to miles instantly — the exact formula, a quick mental maths shortcut, a full conversion chart, and common race and road distances explained.
The Formula
To convert kilometers to miles, multiply by 0.621371.
Miles = Kilometers × 0.621371
One mile is exactly 1.60934 kilometers, so the reverse is also exact: one kilometer is exactly 0.621371 miles. Neither figure is a rounded approximation — it is a fixed, internationally agreed conversion.
Quick mental estimate: multiply by 0.6 (or multiply by 3 and divide by 5) for a rough figure. For 10 km: 10 × 0.6 = 6 miles. The actual answer is 6.21 miles, so this shortcut gives you a close ballpark in a few seconds.
Conversion Chart: 1 km to 100 km
| Kilometers | Miles | Kilometers | Miles |
|---|---|---|---|
| 1 km | 0.62 mi | 15 km | 9.32 mi |
| 2 km | 1.24 mi | 20 km | 12.43 mi |
| 3 km | 1.86 mi | 25 km | 15.53 mi |
| 4 km | 2.49 mi | 30 km | 18.64 mi |
| 5 km | 3.11 mi | 40 km | 24.85 mi |
| 6 km | 3.73 mi | 50 km | 31.07 mi |
| 7 km | 4.35 mi | 60 km | 37.28 mi |
| 8 km | 4.97 mi | 75 km | 46.60 mi |
| 10 km | 6.21 mi | 100 km | 62.14 mi |
Common Race and Road Distances
| Event | Kilometers | Miles |
|---|---|---|
| 5K race | 5 km | 3.107 mi |
| 10K race | 10 km | 6.214 mi |
| Half marathon | 21.0975 km | 13.109 mi |
| Marathon | 42.195 km | 26.219 mi |
| 100K ultramarathon | 100 km | 62.137 mi |
Why the UK Uses Miles but Europe Uses Kilometres
The United Kingdom adopted the metric system for most official purposes but retained miles for road signs and speed limits — a legacy of centuries of imperial measurement that proved difficult to change in everyday road infrastructure.
Most of continental Europe, along with Australia, Canada, and the rest of the world, uses kilometres for road distances. The United States similarly retained miles alongside its broader use of the US customary system.
This means kilometres-to-miles conversion is one of the most frequently needed conversions for travellers — whether reading speed limits on a European road trip in a US-specification car, or comparing race distances across international events.
Convert Kilometers to Miles
Use our free Miles and Kilometres Calculator to convert any distance instantly in either direction — km to miles or miles to km.
Convert any distance between miles and kilometres instantly.
Miles to Kilometres Calculator →