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How long is a marathon?

A marathon is 26.2 miles26 miles and 385 yards, to be exact, or 42.195 kilometres. A half marathon is precisely half of that: 13.11 miles (21.0975 km). The drawing above uses those 26.2 miles as a radius centred on London: drag the map to your own city to see how far you would get if you ran a marathon in a straight line.

From central London, 26.2 miles as the crow flies lands you in Guildford (26.7 mi / 43.0 km). That is the thing the drawing makes obvious: a marathon is not "a long race", it is crossing a whole county.

Why is a marathon 26.2 miles?

Because a royal family wanted to watch the start from its garden. It sounds like a joke, but that is essentially what happened.

The first Olympic marathon, in Athens 1896, covered about 40 km (25 miles) — the road from the town of Marathon to Athens, honouring the legend of the soldier who ran to announce the victory over the Persians. For two decades the distance was approximate and changed every Games: Stockholm 1912 ran 40.2 km and Antwerp 1920 ran 42.75 km.

The figure we use today was born at London 1908. The organisers wanted the race to start at Windsor Castle — on the East Lawn, beside the private terrace, with Edward VII's permission, so the royal children could watch the start — and to finish inside White City Stadium. To bring the finish line in front of the royal box, the final lap of the track was cut to 385 yards (352 m). The total: 26 miles and 385 yards, i.e. 42,195 metres (race records).

In 1921 the IAAF (now World Athletics) standardised the marathon and picked exactly the London 1908 distance. The minutes of that meeting give no reason why: it was simply adopted — which is how half the world came to run a distance set to line up with a grandstand.

26.2 miles is…Equal to
In kilometres42.195 km (42,195 m)
In miles and yards26 miles 385 yards
In half marathons2 (of 13.11 mi / 21.0975 km)
In stepsabout 56,000 (at a 0.75 m stride)
In nautical miles22.8 (of 1,852 m)

A curious detail about the 1908 course

In a straight line, Windsor Castle to White City Stadium is 16.5 miles (26.5 km). The runners covered 26.2 miles: the real course winds, as every city marathon does. That is the difference between the radius this tool draws and the miles actually run — and why no marathon reaches as far as it sounds. Trace a route point by point if you want to measure an actual course.

Pace and finishing times

The worldwide average is around 4 hours 30 minutes. The largest published analysis, covering 19.6 million results from more than 32,000 races (RunRepeat), puts the average finish at 4:29:534:21:03 for men and 4:48:45 for women.

Finish timePaceSpeed
3:006:52 min/mi (4:16 min/km)8.7 mph
3:308:01 min/mi (4:59 min/km)7.5 mph
4:009:09 min/mi (5:41 min/km)6.6 mph
4:30 (the average)10:18 min/mi (6:24 min/km)5.8 mph
5:0011:27 min/mi (7:07 min/km)5.2 mph
6:0013:44 min/mi (8:32 min/km)4.4 mph

At the other end sits the men's world record: 1:59:30, set by Sabastian Sawe at the London Marathon on 26 April 2026 — the first sub-two-hour marathon in a race (World Athletics). That is 4:34 min/mi (2:50 min/km) held for 26.2 miles, at 13.2 mph: roughly the pace most people can hold for 400 metres. For women, the mixed-race record is 2:09:56 (Ruth Chepng'etich, Chicago 2024) and the women-only record 2:15:41 (Tigst Assefa, London 2026).

Race distances, drawn to scale

Click any of them to see it above, centred on London:

RaceDistance
5K3.11 mi (5 km)
10K6.21 mi (10 km)
Half marathon13.11 mi (21.0975 km)
Marathon26.2 mi (42.195 km)
100 km (ultramarathon)62.14 mi (100 km)

Bear in mind these are straight-line radii from the centre of the map, not routes. They are for grasping the scale — how much of your city a marathon spans — not for plotting a course.

Frequently asked questions

How long is a marathon?
A marathon is 26.2 miles: 26 miles and 385 yards, or 42.195 kilometres (42,195 m).
Why is a marathon 26 miles and 385 yards?
Because of the 1908 London Olympic course: it started on the lawn of Windsor Castle and the final lap inside White City Stadium was cut to 385 yards so the finish line sat in front of the royal box, giving 26 miles 385 yards. The IAAF made that distance official in 1921.
How long is a half marathon?
13.11 miles (21.0975 km), exactly half a marathon. It is usually rounded to 13.1 miles or 21 km.
How long does it take to run a marathon?
The worldwide average is about 4 hours 30 minutes (4:29:53 in RunRepeat's analysis of 19.6 million results: 4:21:03 for men and 4:48:45 for women). Breaking 3 hours is considered an advanced-runner mark.
What is the marathon world record?
1:59:30, set by Sabastian Sawe at the London Marathon on 26 April 2026 — the first sub-two-hour marathon in a race, at 2:50 min/km (4:34 min/mi). For women, 2:09:56 (Ruth Chepng'etich, Chicago 2024) in a mixed race.
How many steps are in a marathon?
About 56,000 walking steps at a 0.75 m stride. Running strides are longer (1–1.5 m), so running a marathon can take 30,000–40,000 strides.

Want to keep playing with distances? See how far 10,000 steps is, how long a nautical mile is, or open the distances tool and draw your own. And if areas are more your thing, there is the Hectareometer.

See other distances

← Back to the distances tool