Convert kilometers to miles
1 km = 0.621371192 mi · Formula and table below. Converting the other way? Miles to Kilometers →
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Other units
- Meter (m) 1000
- Kilometer (km) 1
- Decimeter (dm) 10,000
- Centimeter (cm) 100,000
- Millimeter (mm) 1,000,000
- Micrometer (µm) 1,000,000,000
- Nanometer (nm) 999,999,999,999.9999
- Mile (mi) 0.621371192
- Yard (yd) 1093.6133
- Foot (ft) 3280.8399
- Inch (in) 39,370.0787
- Nautical mile (nmi) 0.539956803
- Light year (ly) 1.057001×10⁻¹³
Reviewed on by the Skala Convert team
Multiply kilometres by 0.6214. Ten kilometres is 6.21 miles.
How many miles is a kilometer?
mi = km × 0.621371
A usable approximation: multiply by 6 and divide by 10. 50 km → 30 miles (true: 31.1).
What is the Fibonacci trick for km to miles?
Consecutive Fibonacci numbers — 3, 5, 8, 13, 21, 34 — happen to convert into each other. 5 km is about 3 miles, 8 km about 5 miles, 13 km about 8 miles, 21 km about 13 miles. It works because the ratio between neighbouring Fibonacci numbers approaches 1.618, and a mile is 1.609 km. The error stays under 1%.
How long are 5K, 10K and marathon races in miles?
- 5K = 3.11 miles
- 10K = 6.21 miles
- Half marathon, 21.0975 km = 13.11 miles
- Marathon, 42.195 km = 26.22 miles
The marathon's odd length dates to the 1908 London Olympics, where the course ran from Windsor Castle to the stadium and finished in front of the royal box. That distance became the standard in 1921.
Do the UK and US use miles on road signs?
Road signs and speed limits in the United Kingdom and the United States are in miles. A rental car's speedometer usually shows both, with miles per hour as the large outer scale — see km/h to mph for the speed side.
Where does 0.621371 come from?
It is the inverse of an exact number. NIST Special Publication 811, the US guide to the SI defines the mile as 1,609.344 m, a value fixed by the 1959 international yard; dividing one kilometre by it gives 0.621371… miles, which never terminates. The kilometre itself is a thousand metres, with the prefix rules set out in the SI Brochure published by the International Bureau of Weights and Measures (BIPM).
Formula
Miles = Kilometers × 0.621371192
10 km = 6.213712 mi
Conversion table
| km | mi |
|---|---|
| 1 | 0.621371192 |
| 2 | 1.242742 |
| 5 | 3.106856 |
| 10 | 6.213712 |
| 20 | 12.427424 |
| 25 | 15.53428 |
| 50 | 31.06856 |
| 100 | 62.137119 |
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Frequently asked questions
How many miles is 5 km?
3.11 miles.
How many miles is a marathon?
26.22 miles (42.195 km).
What is a quick way to convert km to miles?
Multiply by 6 and divide by 10, or use neighbouring Fibonacci numbers such as 8 km ≈ 5 mi.