Free km to mi calculator

kilometers to miles converter

Convert road, running, cycling, and travel distances from kilometers to statute miles.

Updated July 20, 2026 Method and assumptions shown below

Convert kilometers to miles

Enter any value to calculate the result instantly.

kilometers to miles formula

Multiply kilometers by 0.6213711922. This follows from one international mile equaling exactly 1.609344 kilometers.

miles = kilometers x 0.6213711922

Conversion table

Use these reference values for a quick comparison. The calculator above accepts positive, negative, decimal, and large values when they are meaningful for the quantity.

kilometersmiles
1 km0.62137119 mi
5 km3.10685596 mi
10 km6.21371192 mi
21.0975 km13.10937873 mi
42.195 km26.21875745 mi
100 km62.13711922 mi

How to use this converter

Enter the source measurement in the first field. CalUnit applies the displayed formula and updates the destination value immediately. You can use decimals and negative values, copy the result into your work, and compare it with the reference table. Keep the original unit beside the starting measurement so another reader can verify the calculation. For a different unit pair, open the complete length conversion guide or the multi-unit length converter.

When this conversion is useful

Road signs and race distances use kilometers in most countries and miles in the United States and United Kingdom. The conversion is for statute miles, not nautical miles.

Accuracy and rounding

The underlying mile definition is exact. For travel estimates, two decimal places are usually enough; mapping and engineering work may need additional digits.

Standards references

CalUnit checks physical unit relationships against authoritative measurement references. See the NIST Guide to the SI conversion factors and the BIPM SI Brochure. Regional cooking measures and digital storage conventions are identified separately because their names can represent more than one definition.