Race distances

How many miles is a 5K run? Race distances in miles and kilometers

By Darrin DeTorres· Published Nov 10, 2026 · Facts checked Nov 10, 2026

How many miles is a 5K run?

A 5K run is 5 kilometers, which is 3.11 miles, so most runners and race directors round it to 3.1 miles. The conversion uses the international mile, which is exactly 1.609344 kilometers. ³ At an easy 12-minute-mile pace, a 5K takes a little over 37 minutes; the median finish across millions of race results is 34:37. ⁷

How many miles is a 10K?

A 10K is 10 kilometers, or 6.21 miles, which is twice the length of a 5K. ³

How many miles is a half marathon?

A half marathon is 21.0975 kilometers, or 13.1094 miles, usually written as 13.1 miles. ²

How many miles is a marathon?

A marathon is 42.195 kilometers, or 26 miles 385 yards, usually written as 26.2 miles. ¹Races longer than a marathon are ultramarathons; World Athletics gives 50 km and 100 km races, and timed events such as 24-hour runs, as examples. ⁶

Miles are calculated from kilometers with the exact factor of 1.609344 km per mile. ³ Finish times are medians from RunRepeat’s calculator, built on 35 million results from more than 28,000 races over the last 20 years worldwide. ⁷ Race counts and fees are Bib Scouts’ own data: every upcoming race on the site on Nov 10, 2026, using each race’s lowest open entry fee at that distance today.

What Bib Scouts’ race data shows

• 5K: 9,344 upcoming races on Bib Scouts as of Nov 10, 2026. The median entry fee today is $30, across the 9,132 races with an open fee listed.
• 10K: 3,719 upcoming races on Bib Scouts as of Nov 10, 2026. The median entry fee today is $45, across the 3,700 races with an open fee listed.
• Half Marathon: 2,927 upcoming races on Bib Scouts as of Nov 10, 2026. The median entry fee today is $65, across the 2,905 races with an open fee listed.
• Marathon: 457 upcoming races on Bib Scouts as of Nov 10, 2026. The median entry fee today is $95, across the 448 races with an open fee listed.

Of the 11,986 upcoming races on Bib Scouts, 6,617(55%) have a scheduled price increase still ahead, so the same race can cost more next month. Each race page shows today’s fee and the date of the next increase.

Other common race distances

Why is a marathon 26.2 miles?

The marathon is named for the legend of the Greek soldier Philippides, who ran from Marathon to Athens. The first Olympic marathon in 1896 was about 40 kilometers. The distance was lengthened for the 1908 London Olympics and fixed at 26 miles 385 yards, or 42.195 kilometers, in 1921. ¹

The half marathon came later: race organizers created it in the 1950s as a shorter alternative to the marathon. ²

Are race courses measured exactly?

In the United States, USATF certifies road courses so that they are accurately measured, and only a certified course counts for records and national rankings. ⁴ A certification expires 10 years after the year it was issued. ⁵

Your GPS watch will usually read a little long, because you rarely run the shortest possible line around every turn that the course was measured on.

Find races by distance

• Races near you, filtered by distance
• Races by state, each with city pages that list races by distance
• Spring half marathons
• City marathon guides: marathons in Eugene, Oregon and marathons in Cleveland, Ohio
• Race guides: Marine Corps Marathon and Rock 'n' Roll San Diego Marathon