Running
How Long Is a Half Marathon?
Updated 1 Nov 2026 · Source: World Athletics half marathon distance ↗
A half marathon is 21.0975 km, or 13.1094 miles: exactly half of a full marathon. Enter your pace per mile below to see how long it will take you.
Worked example
- 21,098 m ÷ 1,609.344 = 13.1094 miles
- 13.1094 × 10:00 per mile = 2:11:06
Half marathon finish time by pace
| Pace per mile | Pace per km | Finish |
|---|---|---|
| 6:00 | 3:44 | 1:18:39 |
| 7:00 | 4:21 | 1:31:46 |
| 8:00 | 4:58 | 1:44:53 |
| 9:00 | 5:36 | 1:57:59 |
| 10:00 | 6:13 | 2:11:06 |
| 11:00 | 6:50 | 2:24:12 |
| 12:00 | 7:27 | 2:37:19 |
| 13:00 | 8:05 | 2:50:25 |
| 14:00 | 8:42 | 3:03:32 |
| 15:00 | 9:19 | 3:16:38 |
| 16:00 | 9:57 | 3:29:45 |
| 18:00 | 11:11 | 3:55:58 |
| 20:00 | 12:26 | 4:22:11 |
Half marathon in other units
| Unit | Value |
|---|---|
| Miles | 13.1094 |
| Kilometers | 21.0975 |
| Meters | 21,097.5 |
| Feet | 69,218 |
| Laps of 400 m | 52.74 |
The distance in every unit
The full marathon is 42.195 km, so half of it is 21.0975 km. In miles that is 13.1094, which race shirts shorten to 13.1. It is also 69,218 feet, or about 52.7 laps of a 400 m track.
That odd decimal comes from the full marathon, which is 26 miles 385 yards. The half simply takes half of it.
How long it takes to run
Finish time is pace times distance. At 9:00 per mile you finish in 1:57:59; at 10:00 per mile, 2:11:06; at 12:00 per mile, 2:37:19. The table lists the finish for paces from 6:00 to 20:00.
The U.S. median half marathon finish in the 2014 race year was 2:02:55 for men and 2:21:22 for women. A median is the middle finisher, so it pictures a typical race day, not a cutoff.
Walking or run-walking 13.1 miles
Some half marathons set a time limit, so read the race rules before you sign up to walk. At 15:00 per mile the walk takes 3:16:38, and at 18:00 per mile it takes 3:55:58.
Mixing running and walking puts you somewhere between those times and a full run. The run walk calculator estimates your finish for any ratio.
The half next to the full marathon
The full marathon is twice the distance, but your finish time will be more than double your half. The common Riegel formula, with its exponent of 1.06, puts a full marathon at about 2.08 times your half marathon time. The race time predictor does that math for you, and real results for a first marathon are often slower still.
How long to train
Beginner half marathon plans are commonly about 12 to 16 weeks, and many assume you can already run a 5K or a few miles. If you are starting lower, give yourself more time. The half marathon training time page goes through it.
Related pages
Half Marathon Pace Chart, Marathon Pace Chart, Running Distance Calculator, How Far Is a 5K?
Questions
Is a half marathon 13 miles?
It is 13.1094 miles, so a little over 13.1.
How long is a half marathon in km?
21.0975 km, often written as 21.1 km.
Why does my watch show more than 13.1 miles?
Courses are measured on the shortest line a runner could take. Few people follow that line exactly, and GPS adds its own small errors, so a reading a bit over 13.1 is normal.
What finish time should I aim for?
Base it on a recent 10K or 5K, then pick a row on the half marathon pace chart to get your pace per mile.
How we calculate: every formula, with its author and year, is on our method page; data sources and their licenses are on sources.
gymnical.com gives estimates from published formulas and public data. It is not medical advice and not a training prescription. Last reviewed November 2026.