A marathon is 42.195 kilometres, or 26.2 miles — precisely 26 miles 385 yards. That distance has been the official standard since 1921, and every certified marathon in the world, from Boston to Berlin to the one in your local park, is measured to it. A half marathon is exactly half: 21.0975 km, or 13.1 miles.
How long it takes depends entirely on who's running. The men's world record is 1:59:30. The typical recreational finisher takes around four and a half hours. A walker at a brisk pace needs about six and a half. This guide covers the distance in every unit, where the strange 26.2 number came from, how long a marathon takes at every pace, how many steps it is, and why your GPS watch will almost certainly tell you that you ran further.
Marathon distance in every unit
| Unit | Marathon | Half marathon |
|---|---|---|
| Kilometres | 42.195 km | 21.0975 km |
| Metres | 42,195 m | 21,097.5 m |
| Miles | 26.2188 mi (26.2) | 13.1094 mi (13.1) |
| Miles and yards | 26 miles 385 yards | 13 miles 192.5 yards |
| Yards | 46,145 yd | 23,072.5 yd |
| Feet | 138,435 ft | 69,217.5 ft |
| 400 m track laps | 105.5 laps | 52.7 laps |
The "26.2" everyone quotes is a round-down of 26.2188 miles. Those extra 385 yards (352 metres) matter more than they sound: at a 10:00/mile pace they are another 2 minutes 11 seconds of running after you have already covered 26 miles.
Why is a marathon 26.2 miles?
The marathon takes its name from the legend of Pheidippides, a Greek messenger said to have run from the battlefield at Marathon to Athens — a distance of around 40 km — to announce victory over the Persians in 490 BC, before collapsing and dying. Whether or not it happened quite that way, it gave the organisers of the first modern Olympic Games in Athens in 1896 their idea: a long-distance race from Marathon to the Olympic stadium, roughly 40 km.
For the next decade the distance drifted from race to race, usually somewhere around 40 km, because no one had agreed on a standard. Then came the 1908 London Olympics. The course was laid out to start at Windsor Castle and finish in the White City stadium, with the finishing line placed in front of the royal box so the royal family could watch the end. The distance that produced was 26 miles 385 yards — 42.195 km.
It stuck. In 1921 the International Amateur Athletic Federation (IAAF, now World Athletics) adopted 42.195 km as the official marathon distance, and it has not changed since. So the answer to "why 26.2 and not 26?" is not physiology or ancient history. It is the length of a particular route through west London, chosen 118 years ago for a good view from a grandstand.
How long is a half marathon?
A half marathon is 21.0975 km, or 13.1 miles (13.1094 to be precise) — exactly half of the full marathon distance. It is the most popular long-distance race in the world by finisher numbers, and for most runners it is the natural stepping stone between a 10K and a full marathon. A typical recreational half takes 2:00–2:20; a typical marathon takes more than double that, because pace fades as distance grows.
How long does it take to run a marathon?
Anywhere from just under two hours to more than eight. The whole range, from the fastest humans alive to a first-timer walking the back half:
| Runner | Finish time | Pace per km | Pace per mile |
|---|---|---|---|
| Men's world record (Sabastian Sawe, London 2026) | 1:59:30 | 2:50 | 4:33 |
| Women's world record (Ruth Chepngetich, Chicago 2024) | 2:09:56 | 3:05 | 4:57 |
| Sub-3 (roughly the fastest 4% of finishers) | 3:00:00 | 4:15 | 6:52 |
| Good club runner | 3:30:00 | 4:59 | 8:01 |
| The classic sub-4 goal | 4:00:00 | 5:41 | 9:09 |
| Median male finisher (large US datasets) | ~4:12 | 5:58 | 9:37 |
| Median finisher, all runners | ~4:27 | 6:20 | 10:11 |
| Median female finisher | ~4:40 | 6:38 | 10:41 |
| Brisk walker (15:00/mile) | 6:33 | 9:19 | 15:00 |
| Typical course cut-off | 6:00–7:00 | 8:32–9:57 | 13:44–16:01 |
A few things to take from that table. The world records are not a useful benchmark for anyone — Sawe's 1:59:30 is a 2:50/km pace that most people could not hold for a single kilometre. The full record history is in marathon world records: the fastest humans in history.
For everyone else, the median finish in large US race datasets sits around 4:25–4:30: men around 4:10–4:15, women around 4:40. "Breaking four hours" is the most common recreational goal precisely because it sits just on the fast side of average. A detailed breakdown by age, gender and experience is in what's the average marathon time?.
Here is how long a marathon takes at every common pace, computed on the exact 42.195 km distance:
| Pace per km | Marathon time |
|---|---|
| 4:00/km | 2:48:47 |
| 5:00/km | 3:30:58 |
| 6:00/km | 4:13:10 |
| 7:00/km | 4:55:22 |
| 8:00/km | 5:37:34 |
| 9:00/km | 6:19:45 |
| 10:00/km | 7:01:57 |
| Pace per mile | Marathon time |
|---|---|
| 7:00/mi | 3:03:32 |
| 8:00/mi | 3:29:45 |
| 9:00/mi | 3:55:58 |
| 10:00/mi | 4:22:11 |
| 12:00/mi | 5:14:38 |
| 15:00/mi | 6:33:17 |
If you want the time for a pace that is not on that list — or the pace you need for a specific goal time — the marathon pace chart covers every pace from 4:00 to 7:00 per km, and the calculator at runpace.co does any pace or time you like.
How long does it take to walk a marathon?
Walking a marathon is entirely possible, and plenty of people do it every year. The arithmetic:
- At 15:00 per mile (a brisk, purposeful walk of 4 mph): 26.2188 × 15 = 393.3 minutes, or 6:33:17.
- At 20:00 per mile (a relaxed 3 mph): 26.2188 × 20 = 524.4 minutes, or 8:44:23.
In metric terms, that is 9:19/km for the brisk walk and 12:26/km for the relaxed one.
The constraint is usually not your legs but the race's clock. Most marathons have a course cut-off of six to seven hours, after which roads reopen and timing mats are packed up; a 6-hour cut-off requires an average pace of 13:44/mile (8:32/km) including every stop. Some big-city marathons allow eight hours, and a handful of walker-friendly events run longer. If you plan to walk, check the cut-off before you enter, and note that a 15:00/mile walk gets you home under a 7-hour limit with about 27 minutes to spare — but not under a 6-hour one.
How many steps is a marathon?
Roughly 32,000 to 42,000 steps, depending on your stride length. Divide 42,195 metres by the length of one step:
| Average step length | Steps in a marathon |
|---|---|
| 1.0 m (shorter stride, walking or slow jog) | 42,195 |
| 1.1 m | 38,359 |
| 1.2 m | 35,163 |
| 1.3 m (longer stride, faster runner) | 32,458 |
Most recreational runners land in the 1.0–1.2 m range at marathon pace, which puts a typical marathon at 35,000–42,000 steps. Faster runners with longer strides take fewer. For comparison, the commonly quoted "10,000 steps a day" is less than a quarter of a marathon — and that is a target for an entire day, not three or four hours.
Is a marathon really exactly 42.195 km?
Yes — and in practice slightly more, by design. Here is how certified courses are measured, and why your watch disagrees.
Course measurement. A certified road course is measured along the shortest possible route a runner could legally take: the inside of every bend, the straightest line between corners. The measurer rides it on a bicycle fitted with a Jones counter, a mechanical revolution counter calibrated against a steel-taped reference distance on the same day. Measurers then add a 0.1% short course prevention factor — an extra 42 metres on a marathon — so that no certified course can ever be found short. The upshot: a certified marathon is at least 42.237 km along the shortest possible line, and any runner who deviates from that line runs further still.
Why your GPS reads long. Almost every runner's watch shows more than 42.2 km at the finish — typically 0.2 to 1 km extra, which at 6:00/km is one to six minutes of running you did not plan for. Two reasons. First, you do not run the tangents: in a crowd of thousands, you weave around people, take the outside of corners, and drift to the side for water stations. Second, GPS drifts. Under tall buildings, in tunnels and under tree cover, the signal bounces and your watch records a jagged path that is longer than the one you actually ran. Big-city marathons with dense skylines — New York, Chicago, London — are notorious for it.
The practical consequence is that your watch's "average pace" will read faster than your official pace, and its mile beeps will drift ahead of the course markers, by half a minute or more at the finish. Pace off the course markers, not the watch, and budget for a few hundred extra metres. The full set of race-day pacing tactics, including how to handle the tangents, is in how to pace a marathon.
Marathon vs other race distances
How a marathon compares with everything from a parkrun to a hundred-miler:
| Race | Kilometres | Miles | Fraction of a marathon |
|---|---|---|---|
| 5K | 5 km | 3.107 mi | 0.12 |
| 10K | 10 km | 6.214 mi | 0.24 |
| 15K | 15 km | 9.321 mi | 0.36 |
| 10 miles | 16.093 km | 10 mi | 0.38 |
| Half marathon | 21.0975 km | 13.109 mi | 0.50 |
| 30K | 30 km | 18.641 mi | 0.71 |
| 20 miles | 32.187 km | 20 mi | 0.76 |
| Marathon | 42.195 km | 26.219 mi | 1.00 |
| 50K | 50 km | 31.069 mi | 1.18 |
| 50 miles | 80.467 km | 50 mi | 1.91 |
| 100K | 100 km | 62.137 mi | 2.37 |
| 100 miles | 160.934 km | 100 mi | 3.81 |
Two things worth noticing. A marathon is more than eight 5Ks, and more than four 10Ks, back to back. And the 20-mile mark — the point where most marathon training plans cap the long run — is only 76% of the race, which is why the last 10 km has a reputation.
How long does it take to train for a marathon?
Most first-time marathoners follow a 16–20 week plan, starting from a base of being able to run comfortably for 30–45 minutes three or four times a week. Experienced runners who already hold a decent weekly mileage typically use 12–16 weeks. The long run builds gradually to 30–35 km (18–22 miles) a few weeks out, and the final two to three weeks are a taper, where volume drops so you arrive at the start line fresh.
If you are starting from zero, build the running habit first and then start a marathon plan — the beginner's guide to running covers the first stage. And for what the final week before the race should look like, see race week: the 7-day taper.
Frequently asked questions
How many miles is a marathon?
A marathon is 26.2 miles — exactly 26 miles 385 yards, or 26.2188 miles. The "26.2" is a rounded figure; the extra 0.0188 miles is about 30 metres.
How many kilometres is a marathon?
A marathon is 42.195 kilometres, which is 42,195 metres. Certified courses are measured with an additional 0.1% safety margin, so the shortest possible route on a certified marathon is at least 42.237 km.
Why is a marathon 26.2 miles and not 26?
Because of the 1908 London Olympics. The course ran from Windsor Castle to the White City stadium, with the finish line in front of the royal box, and that happened to measure 26 miles 385 yards. The distance was adopted as the official standard in 1921 and has stayed ever since. Earlier marathons, including the first modern Olympic marathon in 1896, were around 40 km.
How long is a half marathon?
A half marathon is 21.0975 km, or 13.1 miles (13.1094 to be exact) — exactly half of a full marathon.
How long does it take to run a marathon?
For most people, about four and a half hours: the median finish in large US datasets is around 4:25–4:30, with men around 4:10–4:15 and women around 4:40. A 4:00 marathon is a common recreational goal. The men's world record is 1:59:30 and the women's is 2:09:56.
Can you walk a marathon?
Yes. At a brisk 15:00/mile walk a marathon takes about 6:33; at a relaxed 20:00/mile it takes about 8:44. Check the race's cut-off time first — most are six to seven hours, so a relaxed walk will not make it, while a brisk walk clears a 7-hour limit with time to spare.
Further reading
- What's the average marathon time?
- Marathon world records: the fastest humans in history
- Marathon pace chart: finish times for every pace
- How to pace a marathon: even, negative and positive splits
- Race week: the 7-day taper
- The beginner's guide to running
Work out your own marathon time
Now that you know the distance is exactly 42.195 km, the only question left is how long it will take you. Put a target pace or finish time into the calculator at runpace.co and you'll get your per-kilometre and per-mile splits for the full 26.2 — including the 385 yards at the end.