How long is a marathon? 26.2 miles, and what that distance means for how you train.

The answer: 26.2 miles, or 42.195 kilometers

A marathon is 26.2 miles, which is 42.195 kilometers, which is 26 miles and 385 yards if you want to be exact. Every certified road marathon on the planet is that same distance. The Boston Marathon, the New York City Marathon, the London Marathon, your hometown fall marathon. All 26.2.

The distance is fixed by World Athletics for road racing and has been since 1921. Course certifiers measure the shortest legal running line and add the 0.2 back in, which is why the extra tenths at the end feel so long. You have already crossed 26 by then. The chip mat sits 385 yards further.

In 15 years of coaching, the runners who respect that number and train for it specifically finish the marathon they came for. The runners who treat it as "a really long run" find out at mile 22 that the marathon is a different animal than any training run they have ever done.

Why 26.2 and not a round number

The distance comes from the 1908 London Olympics. The organizers laid out a course from Windsor Castle to the Olympic stadium in Shepherd's Bush. They wanted the finish in front of the royal box. The measured distance came out to 26 miles and 385 yards. That is where the odd 0.2 comes from. A royal viewing preference from more than a century ago, frozen in place.

Before that, marathon distances varied by race. The first modern Olympic marathon in 1896 was about 40 kilometers, roughly 24.85 miles, based loosely on the legendary run from Marathon to Athens. Different races used different distances for years. The 1921 IAAF standardization locked in the London number and every certified marathon since has run the same 26.2.

If you have ever felt that the last 385 yards of a marathon are gratuitous, you are not wrong. They are literally a leftover from a stadium seating chart.

How long is a marathon in different units

Here is the distance in the units most runners see on watches, treadmills, and race maps.

Two conversions to keep in your head. If you train in miles but race an international marathon marked in kilometers, remember that 5 km is about 3.1 miles. When the race clock shows 30 km, you have run about 18.6 miles. That mental math matters when you are tired and trying to work out how much is left.

If your local race publishes splits in kilometers on the tracker, the halfway mark is at 21.1 km, not 13.1 km, and mile 20 sits at 32.2 km. Program your watch fields with whichever unit the course marshals shout.

How long is a half marathon, an ultra, and everything in between

Once you know the marathon distance, the whole road-racing ladder makes sense. The half marathon is exactly half of 26.2. Everything above the marathon is called an ultra, no matter the exact number, so long as it goes over 26.2.

Note that the half marathon is not, physiologically, half a marathon. A half is roughly a threshold effort you hold for about an hour to two hours. The full marathon is an aerobic effort held at a lower intensity for two to six hours. Different fuel systems, different training emphasis, different pacing math. If you are moving up from the half, read the easy-run pace piece first. The number-one reason runners bomb their first full is running the last twelve miles at half-marathon effort by accident.

How long does it actually take to run 26.2 miles

Finish times cover a wide spread. Here is the rough shape of a typical US road marathon field:

• Sub 3:00. Well-trained committed marathoners, typically the front of the field.
• 3:00 to 3:30. Strong recreational marathoners, common in the top quartile of age-group runners.
• 3:30 to 4:15. Where median finishers typically land. Solid runners, usually on their second or third marathon.
• 4:15 to 4:45. Common target for a first-time marathoner with a full training block.
• 4:45 to 5:30. A large portion of the field. First-timers and run-walk finishers.
• 5:30+. Charity runners, walkers, back-of-the-pack finishers. Every certified course allows around six to seven hours to finish.

Whichever band you sit in, the plan is the same shape. What changes is the pace of every workout and the total volume you can absorb. A four-hour marathoner and a three-hour marathoner both train aerobically, both do threshold work, both do a long run with a marathon-paced finish. The numbers just move.

If you want a specific pace for your goal time, the marathon taper protocol covers race-week pacing and the last-three-week plan. To pin down your training paces from a recent race, read what VDOT is and how to use it.

What 26.2 actually feels like, mile by mile

The distance is the same for everyone. The experience of the distance changes at predictable points. If you have never raced a marathon, this is the shape of the day.

The marathon is not a hard 5K stretched out. The last four miles are their own race. Training for the marathon means training for those last four miles specifically. If your long runs never finish at goal marathon pace, mile 23 is going to be a surprise.

The training runway 26.2 requires

Because the distance is fixed, the training runway to prepare for it is largely fixed too, adjusted for where you are starting from. Here are the honest numbers I use with runners.

The most common pattern I see is a runner deciding in June to run a marathon in October. Fourteen weeks. If they are starting from a real base of 15 to 20 miles per week and have run for a year or more, that works. If they are starting from four-mile runs three times a week, it does not. The distance does not scale with willingness. It scales with time under load.

Two rules that hold across every runway:

1. Do not raise weekly mileage by more than 10 percent over the prior week, and take a cutback week every fourth week where you drop volume by 15 to 20 percent.
2. The long run is the anchor. Whatever else your week looks like, protect one long run per week, and progress it steadily so the last four are between 18 and 22 miles.

Full framework for the training block is in the marathon protocol piece. For the philosophy behind why the weekly plan needs to be rewritten to match your recovery, see how the coaching journey works week to week.

What to do tomorrow

If you have decided to run a marathon, do these three things this week and the distance will start to feel less abstract.

1. Pick a race, look at the calendar, and count backwards. Use the runway table above. If the math does not work, move the race, not the plan.
2. Run a real long run this weekend, at a pace slow enough that you could hold a conversation. Distance is 60 percent of whatever your current longest run is. This is your new anchor.
3. Track weekly mileage in the same spot every week. A note in your phone works. Just do not guess. Guessing your training volume is how blocks fall apart in month two.

26.2 miles is a specific number and it responds to a specific kind of preparation. If you want the plan built around you, see how the coaching works and the athletes running it, or apply below.

Written by

Coach Johnny Crain

2:12 marathoner. 4× US Olympic Marathon Trials qualifier. 4× NCAA national champion and 4× NCAA runner-up. Spoke at the RRCA National Convention. Founder and head coach at RunFitCoach, where he coaches every athlete personally.