Half marathon training: a simple 12-week guide
By the Kiki team · Updated · 6 min read
Most runners train for a half marathon (13.1 miles or 21.1 km) in 10 to 16 weeks. Run three or four times a week, keep most runs easy, and build one weekly long run to about 10 to 12 miles (16 to 19 km). Ease off for the final week or two so you start the race fresh.
Before you start
A 12-week plan works best if you can already run about 3 miles (5 km) comfortably and run three times a week. If you're starting from zero, build up to that first. A couch to 5K plan is a good way in.
What a training week looks like
| Day | First half marathon | Chasing a time |
|---|---|---|
| Mon | Rest | Easy run |
| Tue | Easy run | Intervals or tempo run |
| Wed | Rest | Rest |
| Thu | Easy run | Easy run |
| Fri | Rest | Rest |
| Sat | Long run | Long run |
| Sun | Easy run or rest | Easy run |
The long run
Your weekly long run is the key workout. It builds the endurance to go the distance. Start a little longer than your usual run and add about a mile (1 to 2 km) most weeks, with an easier week every three or four weeks. Run it at an easy, chatty pace.
| Week | Long run | Week | Long run |
|---|---|---|---|
| 1 | 4 mi (6 km) | 7 | 8 mi (13 km) |
| 2 | 5 mi (8 km) | 8 | 9 mi (14.5 km) |
| 3 | 6 mi (10 km) | 9 | 10 mi (16 km) |
| 4 | 5 mi (8 km) | 10 | 11 mi (18 km) |
| 5 | 7 mi (11 km) | 11 | 8 mi (13 km) |
| 6 | 6 mi (10 km) | 12 | Race: 13.1 mi |
Easy runs and faster sessions
Most of your running should be easy enough to talk in full sentences. If you're running your first half, that's all you need. If you're chasing a time, add one faster session a week: a tempo run (a steady, comfortably hard effort) or intervals (short, fast repeats with easy jogging between).
Fueling and race-day practice
For runs longer than about 75 minutes, practice taking water and a little carbohydrate, such as an energy gel or sports drink. Use your long runs to test breakfast, shoes and kit. The golden rule: nothing new on race day.
Tapering
In the last week or two, run less but keep a little faster running in. You might feel restless. That's normal. The fitness is already built; the taper lets your legs recover so you can use it.
Race-day pacing
Start slower than your goal pace for the first few miles. If you feel good after halfway, pick it up gradually. A strong finish feels far better than hanging on.
Common questions
- How many weeks do I need to train for a half marathon?
- Most plans run 10 to 16 weeks. Twelve weeks suits runners who can already run about 3 miles (5 km) comfortably.
- How long should my longest run be before a half marathon?
- Most runners peak at 10 to 12 miles (16 to 19 km) two or three weeks before the race. You don't need to run the full 13.1 miles in training.
- How many days a week should I run?
- Three or four. First-time half marathoners do well on three runs a week; runners chasing a time often run four or five.
This guide is general information, not medical advice. If you have pain, an injury or a health condition, talk to a qualified professional.