KM to Miles Calculator
Convert kilometres to miles instantly. Perfect for understanding international race distances, road trips and travel — accurate to the exact conversion factor every time.
How to Convert Kilometres to Miles
Converting kilometres to miles is straightforward once you know the conversion factor. Need to convert the other way? Use our Miles to KM Calculator instead. One kilometre equals 0.621371 miles — since kilometres are a smaller unit than miles, the number of miles will always be smaller than the number of kilometres you started with.
Example: 5 km (parkrun) × 0.621371 = 3.11 miles
This calculator handles the conversion instantly — enter any distance in kilometres above to see the exact equivalent in miles.
Kilometres to Miles — Understanding International Distances
If you're from a country that uses miles (the US, UK, or a handful of others) and you're reading about a distance given in kilometres — our KM/H to MPH Calculator handles the same conversion for speed — whether it's a road trip abroad, a race distance, or a news article — this conversion helps put the number into a scale you're more familiar with.
| Kilometres | Miles |
|---|---|
| 5 km (parkrun) | 3.11 miles |
| 10 km | 6.21 miles |
| 21.1 km (half marathon) | 13.11 miles |
| 42.2 km (marathon) | 26.22 miles |
| 100 km | 62.14 miles |
General Kilometres to Miles Conversion Table
| Kilometres | Miles |
|---|---|
| 10 km | 6.21 miles |
| 25 km | 15.53 miles |
| 50 km | 31.07 miles |
| 100 km | 62.14 miles |
| 500 km | 310.69 miles |
| 1000 km | 621.37 miles |
Why Does Most of the World Use Kilometres?
The kilometre is part of the metric system, developed in France in the 1790s and gradually adopted as the international standard for measurement. Today nearly every country in the world uses kilometres for road distances, running events and everyday measurement — with the United States being the largest and most notable exception, still using miles for road distances.
The UK sits in an unusual middle ground — using miles for road signs and speed limits, but kilometres and metric units for almost everything else including sport, science and general measurement. If you're also converting metric weights, try our KG to Pounds Calculator.
Common Uses for Converting Kilometres to Miles
- Reading international road signs. If you're driving in Europe, Australia, or almost anywhere outside the US, distances are shown in kilometres.
- Understanding race distances. Overseas marathons, 10Ks and cycling events are typically measured in kilometres.
- Vehicle specifications. Speedometers, fuel economy figures and range estimates in many countries use km rather than miles.
- Geography and news. Understanding distances mentioned in international news, travel guides and geography content — our Temperature Converter is equally useful when travelling internationally.
FAQs
How many miles is a kilometre?
One kilometre equals 0.621371 miles. Multiply your distance in kilometres by 0.621371 to get miles.
How do I convert km to miles for running?
Enter your distance in kilometres into the calculator above. Common conversions include: 5 km = 3.1 miles, 10 km = 6.2 miles, 21.1 km (half marathon) = 13.1 miles, 42.2 km (marathon) = 26.2 miles.
Is the km to miles conversion exact?
Yes — one kilometre equals exactly 0.6213712 miles, so this conversion is always precise, not an approximation.
Why does most of the world use kilometres?
Kilometres are part of the metric system, adopted by nearly every country except the United States, which still uses miles for road distances.
How do I convert 100 km to miles?
Multiply 100 by 0.621371, which equals 62.14 miles. Use the calculator above for instant results with any distance.
What is 42.2 km in miles?
42.2 km (a marathon) equals 26.22 miles. This is one of the most commonly searched international race distance conversions.
Is this calculator free?
Yes — completely free, no sign-up required. Enter any distance in kilometres for an instant result in miles.