How long is a marathon and how long does it take to run one?

London Marathon runners
(Image credit: Shutterstock)

If you’ve been googling ‘how long is a marathon?’ the chances are you’ve been inspired by marathon season — in the next month, the London Marathon, Chicago Marathon, and New York City Marathon are all taking place. 

The London Marathon is first — it takes place on Sunday (October 3) — and if you’ve been swept up in marathon fever, here’s everything you need to know about the distance. 

How long is a marathon? 

A marathon is 26.2 miles or 42.19 kilometers. 

It’s an awfully specific distance for a reason and wasn’t set until the 20th century. The modern marathon was inspired by the legend of an ancient Greek messenger in 490 B.C., who raced from Marathon to Athens (a distance of nearly 25 miles) with news of a Greek victory over an army of Persians. After finishing the run, he collapsed and died. To commemorate the achievement the 1896 Olympic marathon was 40 kilometers. 

In 1908, however, during the Olympic Games in London, the course was extended, allegedly because Queen Alexandra wanted the race to start on the lawn of Windsor Castle so the younger members of the British Royal Family could watch the runners. 

The race finished in front of the royal box at the Olympic stadium, which happened to be 26.2 miles away. 

How long, on average, does it take to run a marathon? 

According to data that looked at race results from more than 70,000 events from 1986 to 2018, the average marathon finish time for runners in the United States is 4 hours and 42 minutes. The average male marathon finish time in the US is 4 hours and 31 minutes and the average female marathon finish time in the US is 4 hours and 57 minutes. 

The men’s world record for the marathon distance is a time of 2:01:39, set by Eliud Kipchoge at the 2018 Berlin Marathon. The female world record in the marathon is 2:14:04, set by Brigid Kosgei at the 2019 Chicago Marathon. 

Swipe to scroll horizontally
Fastest average marathon finish time by nation
Country Average marathon finish time
Spain3:53
Switzerland3:55
Portugal 3:59
Ukraine 3:59
Norway4:01
Slovenia 4:02
Belgium 4:03
Luxembourg4:04
Iceland4:04
Malta 4:07

How long, on average, does it take to walk a marathon? 

If you were to walk 26.2 miles, it’s likely that it would take you between six and nine hours. Walking at a brisk pace, you’d probably cross the finish line in 6-7 hours, but at a natural walking pace, it would take much longer. 

How long is a half marathon? 

A half marathon is 13.1 miles or 21.09 kilometers. 

According to the same data, collected by RunRepeat, for runners from the US, the average half marathon finish time is 2 hours and 10 minutes. To drill down further, the average male runner from the US will run a half marathon in 2 hours and 2 minutes, whereas the average female runner will cross the finish line in 2 hours and 16 minutes. 

The male world record for the half marathon distance is 57:32, run by Kibiwott Kandie at a half marathon that was part of the Valencia Marathon in 2020. The female world record for the half marathon is 1:04:31, set by Ababel Yeshaneh in the 2020 Ras Al Khaimah Half Marathon. 

How long is a 10K?

A 10K is 10 kilometers long, or 6.21 miles. 

The average 10K finish time in the US is 1 hour and 1 minute. For men, the average time is slightly faster, at 58 minutes and for women, it’s slightly slower at 1 hour and 6 minutes. The world record in the 10K is 26 minutes and 11 seconds for men, set by Joshua Cheptegei, or 29 minutes and 17 seconds for women, set by Almaz Ayana. 

How long is a 5K? 

A 5K is five kilometers long, or 3.1 miles.

The average 5K time for runners in the US is 39 minutes. For men, the average is faster, at 35 minutes and for women, the average is slower at 41 minutes. The world record in the 5K is 12:35.36 for men, set by Joshua Cheptegei, and 14:06.62 for women, set by Letesenbet Gidey. 

Jane McGuire
Fitness editor

Jane McGuire is Tom's Guide's Fitness editor, which means she looks after everything fitness related - from running gear to yoga mats. An avid runner, Jane has tested and reviewed fitness products for the past five years, so knows what to look for when finding a good running watch or a pair of shorts with pockets big enough for your smartphone. When she's not pounding the pavements, you'll find Jane striding round the Surrey Hills, taking far too many photos of her puppy. 

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