How many miles are in a kilometer?

1 km = 0.621371 mi. To convert any amount, multiply by 0.621371.

How do you convert kilometers to miles?

Multiply the number of kilometers by 0.621371 to get miles. The formula is shown in the "How it's calculated" section above.

Where does the conversion factor come from?

It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.

Unit converter — Length

Kilometers to miles converter

Convert kilometers (km) to miles (mi). Source-cited conversion factor, exact to the displayed precision.

Results are mathematically exact for the displayed precision. How we calculate.

How it's calculated

Convert kilometers to miles— the formula

Kilometers convert to miles by multiplying by the published conversion factor. The factor below is exact to the precision shown, sourced from the citation under the formula.

mi = km × 0.621371

km = mi × 1.6093

SI base unit (BIPM). US customary lengths from the 1959 international yard agreement: 1 yd = 0.9144 m exactly, 1 in = 25.4 mm exactly, 1 mi = 1609.344 m exactly.

Questions

Frequently asked questions

How many miles are in a kilometer?
1 km = 0.621371 mi. To convert any amount, multiply by 0.621371.
How do you convert kilometers to miles?
Multiply the number of kilometers by 0.621371 to get miles. The formula is shown in the "How it's calculated" section above.
Where does the conversion factor come from?
It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.