Kilometers to Miles Converter

The conversion factor

One kilometer equals 0.621371 miles. The calculator above multiplies whatever you enter by that factor and rounds the result to two decimal places. For example, a 5-kilometer run works out to 5 × 0.621371 = 3.11 miles — the same number a race organizer would use to relabel a "5K" as a "3.1-mile" route.

Where the factor comes from

A mile is defined as exactly 1,609.344 meters (the international mile, agreed in 1959). Dividing 1,000 meters by 1,609.344 gives 0.6213711922...; the tool truncates that to six decimal places, which is precise enough that the rounding error never shows up in a two-decimal answer.

A few reference points

When this matters

Road signs, speed limits, and odometers switch between km and miles depending on the country — the US, UK, and Liberia are the main holdouts still posting distances in miles. If you're reading a European car's spec sheet (fuel economy, top speed, range) or planning a hike using a metric trail map, this is the factor you need in both directions; for the reverse conversion, divide by 0.621371 instead of multiplying.