Half Marathon Distance: How Many Miles Is a Half Marathon?
How long is a half marathon in km and miles? Exact distance (21.1 km / 13.1 miles), pacing tables, and links to half marathon races and training plans.
· 6 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 **how many miles is a half marathon**, the short answer is **13.1 miles**. If you are new to the distance, the half marathon 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 1:20 to 2:30, see our [pace chart guide](/blog/half-marathon-pace-chart). Use the [pace calculator](/tools/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.
**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 Brisbane](/races/australia/brisbane)
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 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**.
**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 marathon time](/blog/average-marathon-time) for context when planning longer goals.