RunPackGuides · 7 min read
Half marathon training plan: 12 weeks for beginners (free)
A free 12-week half marathon training plan for beginners and returning runners: long runs from 8 to 19 km, one quality session a week, paces and race-day tips.
Twelve weeks is a comfortable build to your first half marathon (21.1 km), or back to one after a break. The plan assumes you can run 5K, or about 30–40 minutes, without stopping. It uses three runs a week, with an optional fourth.
The plan
| Week | Quality session | Easy run | Long easy run |
|---|---|---|---|
| 1 | 6 × 2 min brisk, 2 min easy | 30 min | 8 km |
| 2 | 15 min tempo | 30 min | 9 km |
| 3 | 5 × 3 min at 10K effort, 2 min jog | 35 min | 10 km |
| 4 | Fartlek, 25 min | 30 min | 8 km (lighter week) |
| 5 | 20 min tempo | 35 min | 12 km |
| 6 | 4 × 1.6 km at 10K pace, 2 min jog | 40 min | 13 km |
| 7 | 2 × 12 min tempo, 3 min jog | 40 min | 14 km |
| 8 | Easy fartlek, 30 min | 35 min | 11 km (lighter week) |
| 9 | 25 min tempo | 40 min | 16 km |
| 10 | 3 × 3 km at goal pace, 3 min jog | 40 min | 18 km |
| 11 | 20 min tempo | 40 min | 19 km, last 5 at goal pace |
| 12 | 4 × 1 km at goal pace | 25 min | Race day |
Always warm up before quality sessions. Weeks 4 and 8 are lighter on purpose: that’s when your body catches up.
Paces
- Long runs: easy and conversational. Slower than you think. Walk breaks are fine. More on long runs.
- Goal pace: your target time divided by 21.1. The half marathon pace chart lists it for 1:20 to 3:00, with checkpoint splits.
- Tempo: comfortably hard. Tempo runs explained.
Pick a realistic goal from a recent 10K with the pace calculator; for a first half, finishing comfortably is a great goal.
Fuel and water
Practise on long runs over 75 minutes: carry water, and try the gels or snacks you’ll use on race day. Race day is not the time to try anything new.
Race day
- Start slower than goal pace for the first 2–3 km; crowds and adrenaline make it feel easy.
- Pass 10 km at or just behind your goal split, then aim for an even or negative split.
- Drink at the water stations early, before you’re thirsty.
Train with friends
Twelve weeks is long. Pick a race with friends, follow the same plan at your own paces, and run the long run together. More in half marathon training with friends. RunPack, our free iPhone app, puts everyone’s runs in a private feed for your crew, so the weeks you train apart still feel shared.
General guidance, not medical advice.