Km to miles

The exact conversion

Kilometers to miles is the road and race conversion. The mile on this page is the international statute mile, exactly 1.609344 kilometers, or 5,280 feet. It is not the nautical mile of 1.852 kilometers, which is used at sea and in aviation. A kilometer is shorter than a mile, so the mile number is smaller: 5 kilometers is 3.11 miles, and 10 kilometers is 6.21 miles.

The formula used above is mi = km ÷ 1.609344. Both boxes stay in step, so you can start from either unit. Results are rounded for display; the factor itself is the legal definition, not a rounded shortcut.

Worked examples

Each line is the same formula with a new starting number. You can match it against the converter by typing the value on the left.

• 1 kilometer: 1 ÷ 1.609344 = 0.6214 miles.
• 5 kilometers: 5 ÷ 1.609344 = 3.1069 miles.
• 42.195 kilometers: 42.195 ÷ 1.609344 = 26.2188 miles.

Where the rounding matters

A marathon is 42.195 kilometers by the standard course distance. Dividing by 1.609344 gives 26.219 miles, which is why the race is called 26.2 miles. A half marathon, 21.0975 km, is 13.109 miles. For a drive, multiplying kilometers by 0.62 is a fair mental estimate: 100 km is about 62 miles, and the exact figure is 62.14 miles. The error in that shortcut is under half a percent.

If the result is larger than the kilometers you typed, the conversion ran toward kilometers instead of miles. Five miles is a bit over 8 kilometers, which is the Fibonacci memory trick in the other direction: 5 miles ≈ 8 km, so 8 km ≈ 5 miles and 5 km ≈ 3.1 miles. Use the miles to km page when the sign, the odometer, or the race is already in miles.

Conversion table: km to miles