How many miles is 1 kilometer?
1 kilometer is 0.621371 miles, or about 0.6 miles.
Length conversion
Kilometers to miles converter calculator
Last updated:
1 kilometer equals 0.621371 miles. To convert, multiply kilometers by 0.621371 (or divide by 1.60934). 5K is 3.10686 miles; a marathon (42.195 km) is 26.2 miles.
Featured kilometers to miles converter answer
Kilometers
1 km
miles converter
0.6214 mi
Formula: 1 kilometer = 0.621371 miles. Open the live calculator to convert any value.
Formula
1 kilometer = 0.621371 miles
The factor 0.621371 comes from the definition 1 mile = 1.609344 kilometers exactly, which was set in the 1959 international yard agreement. The reciprocal gives the km-to-mile factor.
Common values
| From | To |
|---|---|
| 1 km | 0.6214 mi |
| 2 km | 1.2427 mi |
| 5 km | 3.1069 mi (5K race) |
| 8 km | 4.9710 mi |
| 10 km | 6.2137 mi (10K race) |
| 15 km | 9.3206 mi |
| 21.0975 km | 13.1094 mi (half-marathon) |
| 25 km | 15.5343 mi |
| 42.195 km | 26.2188 mi (marathon) |
| 100 km | 62.1371 mi |
Background
The international mile (5,280 feet) traces back to Roman mille passus, 1,000 paces. The metric kilometer arrived with the French Revolution. Both systems coexist globally: nearly all road signs outside the US, UK, and a few Caribbean nations use kilometers.
Common use cases
- Convert international route distances into miles for US-focused travel planning.
- Translate race distances like 5K and 10K into familiar mile equivalents.
- Compare driving, cycling, or running distances across metric and imperial sources.
Frequently asked questions
How long is a 5K in miles?
5 kilometers is 3.10686 miles. A 10K is exactly twice that: 6.21371 miles.
How many miles is a marathon?
A marathon is 42.195 kilometers, which equals 26.2188 miles. The 26.2-mile distance is named for the 1908 London Olympics route.
What's the quick way to estimate km to miles?
Multiply by 0.6 for a rough estimate, or use the Fibonacci coincidence: consecutive Fibonacci numbers approximate km-to-mile pairs. 5 km is about 3 mi, 8 km is about 5 mi, 13 km is about 8 mi.
Are kilometers and kilometres the same thing?
Yes. 'Kilometre' is the SI spelling used in British English and most of the world; 'kilometer' is the American English spelling. Both refer to the same SI base-unit derivative.
More length conversions
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