| Factor | Half Marathon | Marathon |
|---|---|---|
| Distance | 21.1 km | 42.2 km |
| Training weeks | 10-14 | 16-20 |
| Peak long run | 16-18 km | 32-35 km |
| Fuelling during | Optional (under 1:45) | Essential |
| Recovery time | 1-2 weeks | 3-4+ weeks |
| Finish time (avg) | 1:45-2:30 | 3:45-5:30 |
| Injury risk | Lower | Higher (volume) |
Choose Half Marathon when…
You want a serious challenge without 4-5 months of intensive training, are new to endurance racing, want a distance where pacing errors are less catastrophic, or want to race more frequently in a year.
Choose Marathon when…
You've completed a half and want the ultimate test, are drawn to the iconic nature of the marathon, can commit 16-20 weeks of structured training, or are targeting London, Boston, Chicago, New York or Berlin.
Gear for both
GPS Running Watch
Track pace, HR and distance for both half and full marathon training.
Check price on AmazonRunning Training Plans Book
Structured plans for half and full marathon distances.
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FAQ
Can I do a marathon without doing a half first?
Yes — but completing a half marathon first gives you valuable race experience (pacing, nutrition, race-day logistics) that makes the marathon safer and more enjoyable. Most coaches strongly recommend it.
How much slower is a marathon than a half?
Typically 10-15% slower per kilometre than half marathon pace for trained runners. A 1:45 half marathoner typically runs 3:45-4:00 for the marathon. Untrained runners slow more dramatically.
What training plan do I need for a first half marathon?
A standard first half-marathon plan runs 10–14 weeks with 3–4 runs per week, peaking at a long run of 18–20km approximately 2–3 weeks before race day. Most plans include one easy long run, one mid-week longer run, and one or two shorter sessions. If you can currently run 5km comfortably, 12 weeks is a realistic timeline for a half-marathon finish. The goal for most first-timers should be completion, not time.