Maybe you just signed up, or you're still on the fence. Either way, you want to know what you're getting into: how far is it exactly, how long do other runners take, and what pace matches the time you have in mind? This article lays out the numbers, along with where they come from. Want to work with your own goal time right away? Use the half marathon pace calculator. Looking for a training plan? See the half marathon training plan.
01 · How many miles?How many miles is a half marathon?
A half marathon is 13.1 miles, or 21.0975 kilometers. It's exactly half of the 26.2-mile (42.195 km) marathon. Race shirts and bumper stickers say 13.1, and some events round to 21.1K or 21K, but a certified half marathon course is always the full 21.0975 kilometers.
If your watch reads 21.4 km13.3 mi or 21.6 km13.4 mi at the finish, the course wasn't long. Certified courses are measured along the shortest possible route, cutting every corner on the inside. In a crowded race, you weave around other runners, take turns wider, and drift to the side for a cup of water. GPS watches also lose some accuracy between tall buildings and under trees. For pacing, that means checking your time against the distance markers on the course, not only against your watch.
For comparison, a half marathon is a little more than twice as long as a 10K. At an easy pace, you'll be out there for two hours or more, and that time on your feet is what makes it so different from a 10K that simply takes a few minutes longer.
02 · Average timesHow long does it take to run a half marathon?
The short answer: most runners take between an hour and a half and three hours, and the runner in the middle of the pack finishes in about 2 hours and 15 minutes. The figures below come from the largest public analyses of race results. They describe recreational runners; the world's best cover the distance in under an hour.
Average time for men and women
For its report The State of Running (2019, updated in 2024), RunRepeat, a running-data research site, analyzed 107.9 million race results from more than 70,000 events between 1986 and 2018, excluding elite runners. A second RunRepeat analysis of about 35 million results from more than 28,000 races shows what share of runners finished faster or slower than a given time. That gives the median: the time by which exactly half of all runners have finished.
| Average (1986–2018) | Median | |
|---|---|---|
| Men | About 2:00 | 2:00 (1:59:48) |
| Women | About 2:14 | 2:24 (2:24:03) |
| All runners | – | 2:15 (2:14:59) |
The average is calculated from the average pace in the first report; the median comes from the second analysis. The two differ by ten minutes for women because they are based on different sets of results. Both sets are largely made up of US races. Read the numbers as a general picture, not as a standard for the half marathon in your town. A fast, flat course, the weather, and the type of event all make a big difference to the average.
From the same RunRepeat percentile table:
So a sub-2-hour half marathon puts you ahead of most of the field. It's a great goal, but certainly not a requirement.
Average time by age
Age matters less than many runners think. In a study in Deutsches Ärzteblatt International (Leyk and colleagues, 2010), German researchers analyzed more than 900,000 finish times of marathon and half marathon runners aged 20 to 79. They found no clear decline in performance before age 55, and only a gradual one after that. A quarter of the runners aged 65 to 69 were even faster than half of the runners aged 20 to 54.
The typical half marathoner isn't in their twenties, either: in the RunRepeat data, the average age rose to 39. A Swiss analysis of more than 385,000 half marathon results from 1999 to 2019 (Knechtle and colleagues, Scientific Reports, 2023) also shows that the gap between men and women narrows with age, from the 20–24 age group to the 65–69 age group. In that data, about three in ten finishers were women.
What this means for you: if you start at 40 or 50, there's no need to lower your expectations in advance. Your training matters more than your birth year.
What time can you expect?
An average says little about what you can run. A better predictor is a recent race at a shorter distance. The race time predictor converts your 10K time into an expected half marathon time:
| Your 10K time | Expected half marathon |
|---|---|
| 45 minutes | About 1:40 |
| 50 minutes | About 1:51 |
| 55 minutes | About 2:02 |
| 60 minutes | About 2:13 |
| 65 minutes | About 2:24 |
| 70 minutes | About 2:35 |
This prediction assumes you've also trained for the longer distance, with long runs in your build-up. If a 10K is the longest you've run so far, your first half marathon will usually take longer than the table suggests. For a first half marathon, finishing at an even pace is a perfectly good goal. You can read the background of this conversion in the article on Zones and Quality (VDOT).
03 · Pace chartWhat pace do you need for your goal time?
Once you know the finish time you want, the pace follows: divide your goal time by the distance. This chart lists common goal times. Paces are rounded to 5 seconds; the halfway split is exact.
| Goal time | Average pace | Halfway |
|---|---|---|
| 1:30 | 4:15 min / km6:50 min / mi | 45:00 |
| 1:40 | 4:45 min / km7:40 min / mi | 50:00 |
| 1:45 | 5:00 min / km8:00 min / mi | 52:30 |
| 1:50 | 5:15 min / km8:25 min / mi | 55:00 |
| 2:00 | 5:40 min / km9:10 min / mi | 1:00:00 |
| 2:15 | 6:25 min / km10:20 min / mi | 1:07:30 |
| 2:30 | 7:05 min / km11:25 min / mi | 1:15:00 |
| 2:45 | 7:50 min / km12:35 min / mi | 1:22:30 |
| 3:00 | 8:30 min / km13:45 min / mi | 1:30:00 |
Because of the rounding, running exactly the pace in the chart can put you just over your goal. At exactly 5:15 min / km8:25 min / mi, for example, you'd finish just over 1:50 instead of under it. If you really want to break a barrier, run a few seconds per mile faster. In a race, you'll also often cover a bit more than the official distance, as explained above.
How to calculate your pace yourself
To work out the pace for any other goal time, take three steps:
The half marathon pace calculator does this faster and also shows your split at every mile or kilometer. If you want to run the second half a little faster than the first, the split calculator builds a negative-split plan. For most runners, an even pace is the safest choice: a start that's too fast often costs you later in the race.
Pace and effort on race day
The pace in the chart is an average for a flat course in good weather. In heat, wind, or hills, run by feel and keep your effort steady rather than your pace. Half marathon pace feels comfortably hard for most runners: you can say a few words, but you can't hold a conversation. How that effort relates to your other training paces is explained in heart-rate zones explained.
You'll be running for one and a half to three hours, so fueling counts too. A sports drink or gel you've already used in training helps in the second hour. What to eat in the days before and on race morning is covered in race-day nutrition.
04 · How long to train?How long should you train for a half marathon?
That depends mostly on what you're running now. A half marathon doesn't require you to get faster; it requires you to keep going for longer. That's why you look at your current week, not just your fastest 10K.
| Where you are now | Common build-up |
|---|---|
| You (almost) don't run yet | At least 16 weeks, often longer: first a base up to 5K and 10K |
| You run twice a week, about 15 km9.3 mi in total | 16 weeks, two runs a week |
| You run three times a week and an easy 90-minute run feels familiar | 12 weeks, three runs a week |
| You run a 10K in about 54 minutes and want to break 2 hours | 12 weeks, three or four runs a week |
If you're starting from zero, first build a running base with the couch to 5K plan, then with the 10K training plan. Back to back, those separate plans take six months or more, and that's not a detour: your muscles, tendons, and bones need that time to get used to running. How to start running explains how to approach the first weeks. A personalized plan can also build from (almost) no running to a half marathon in one go. It needs at least 16 weeks for that, and more than two running days a week at beginner level.
If you already run regularly, choose the half marathon training plan: 12 weeks with three runs a week, or 16 weeks with two. The longest run in those plans is 17 km10.6 mi, so you don't need to run 13.1 miles before race day. The long runs, a few tempo workouts, and the lighter final weeks, called the taper, prepare you together.
If you have a time goal, the sub-2-hour half marathon training plan fits if you currently run a 10K in about 54 minutes. A 1:45 or 1:30 goal calls for faster training paces and usually more weekly mileage. To learn which workouts make you faster, read how to improve running speed.
Summary and next step
A half marathon is 13.1 miles (21.0975 km). Men finish in about 2 hours on average, women in roughly 2:15 to 2:25, and half of all runners finish within about 2:15. A 2-hour finish takes an average of 5:40 min / km9:10 min / mi. With an existing running base, you train 12 to 16 weeks for it. A personalized plan works from your goal time, your current running week, and the days you have available.
