Half Marathon Distance: 13.1 Miles / 21.1 KM Exact (2026)
Half a marathon distance is exactly 21.0975 km (13.1094 miles). Official conversion, pace tables, training links, and where to find half marathon races.
· 7 min read · Training
A half marathon is **21.0975 kilometres**, or **13.1094 miles**. Most race websites round that to **21.1K** or **13.1 miles**, which is close enough for training and pacing.
If you searched **half a marathon distance** or **how many miles is a half marathon**, the short answer is **13.1 miles / 21.1 km**. If you are new to the distance, the half sits in a sweet spot: long enough to feel like a real endurance event, but short enough to recover within a week or two if you train sensibly.
Half marathon distance in km and miles
| Unit | Exact | Common rounding | | --- | --- | --- | | Kilometres | 21.0975 km | 21.1 km | | Miles | 13.1094 mi | 13.1 miles |
How half marathon pace translates to finish time
| Finish time | Pace per km | Pace per mile | | --- | --- | --- | | 1:30 | 4:16/km | 6:52/mi | | 1:45 | 4:58/km | 8:00/mi | | 2:00 | 5:41/km | 9:09/mi | | 2:15 | 6:24/km | 10:18/mi | | 2:30 | 7:06/km | 11:27/mi |
For a full **half marathon pace chart** from 1:15 to 3:00, see our [pace chart guide](/blog/half-marathon-pace-chart). Use the [half marathon pace calculator](/tools/half-marathon-pace-calculator) if you want checkpoint splits for a specific goal.
Training for your first or next half
A structured build matters more than squeezing in random long runs. Start with a [half marathon training plan for beginners](/plans/half-marathon) that adapts to your current mileage and available days.
If you are still building from shorter distances, the [5K planner](/plans/5k) or [Couch to 5K plan](/plans/couch-to-5k) can be a better entry point before jumping to 21.1K.
Compare your target against [average half marathon time by age](/blog/average-half-marathon-time) and [what counts as a good half marathon time](/blog/good-half-marathon-time) before you lock a race-day goal.
**Find races:** Browse [half marathon races](/races/half) worldwide, or narrow by city:
- [Half marathons in London](/races/united-kingdom/london) - [Half marathons in Manchester](/races/united-kingdom/manchester) - [Half marathons in Melbourne](/races/australia/melbourne) - [Half marathons in Sydney](/races/australia/sydney) - [Half marathons in Brisbane](/races/australia/brisbane) - [Half marathons on the Gold Coast](/races/australia/gold-coast) - [Half marathons in Adelaide](/races/australia/adelaide) - [Half marathons in Perth](/races/australia/perth)
Pair race discovery with weekly parkrun consistency through our [parkrun directory](/parkruns) if you want a low-pressure Saturday benchmark during your build.
Half marathon vs full marathon distance
| Race | Exact distance | Common shorthand | | --- | --- | --- | | Half marathon | 21.0975 km / 13.1094 mi | 21.1K / 13.1 | | Marathon | 42.195 km / 26.2188 mi | 42.2K / 26.2 |
A half is exactly half of the marathon standard. That is why pacing tables scale cleanly: a **2:00 half** and a **4:00 marathon** share the same **5:41/km** even pace on a flat course (though marathon fatigue means most runners cannot hold half pace for the full 42.2 km without specific training).
Half marathon distance FAQs
**How many miles is a half marathon?** 13.1094 miles, usually rounded to **13.1 miles**.
**How long is a half marathon in km?** 21.0975 km, usually rounded to **21.1 km**.
**What is half a marathon distance in km?** **21.0975 km** — the same official half marathon distance used worldwide.
**Is a half marathon the same as 21K?** Almost. Officially it is 21.0975 km, so 21K is a slight underestimate.
**How long does it take to run a half marathon?** Most recreational finishers land between 1:45 and 2:30, depending on experience and course profile. See [average half marathon time](/blog/average-half-marathon-time) for age-group context, then set splits with the [half marathon pace chart](/blog/half-marathon-pace-chart).