Sub 3:45 marathon pace
To run a marathon under 3:45:00 you need to average 5:19 per kilometre, or 8:34 per mile. Here are the splits, a pace band, the paces to train at and the fitness you need before race day.
Pace band
Even-pace elapsed times. Copy them to your wrist, or get a printable band in the free Race Pace Plan.
Splits
Even pace versus a 1 % negative split. Both finish exactly on 3:45:00; aim to cross the line a little inside it.
| Point | Even pace | 1 % negative |
|---|---|---|
| 5 km | 26:40 | 26:48 |
| 10 km | 53:19 | 53:35 |
| 15 km | 1:19:59 | 1:20:23 |
| 20 km | 1:46:39 | 1:47:11 |
| Half | 1:52:30 | 1:53:04 |
| 25 km | 2:13:19 | 2:13:46 |
| 30 km | 2:39:58 | 2:40:18 |
| 35 km | 3:06:38 | 3:06:50 |
| 40 km | 3:33:18 | 3:33:21 |
| Finish | 3:45:00 | 3:45:00 |
Race times that match this goal
Equivalent performances from Riegel's formula. If you can run these, sub 3:45 is realistic with the right training.
Training paces for sub 3:45
| Run type | Pace /km | Zone | Typical session |
|---|---|---|---|
| Recovery | 6:41–7:30 | Zone 1 | Between hard days, 20–40 min |
| Easy and long runs | 6:02–6:41 | Zone 1–2 | Most of your weekly volume |
| Marathon pace | 5:17–5:23 | Zone 2–3 | Long-run segments of 8–20 km |
| Threshold | 4:52–5:03 | Zone 3–4 | 3 × 10 min or 20–30 min steady |
| Interval (VO2max) | 4:33–4:42 | Zone 4–5 | 5 × 1000 m, 3 min jog |
| Repetition | 4:20–4:26 | Zone 5 | 8 × 200–400 m, full recovery |
What it takes
Most runners who break 3:45 in the marathon build to about 45–65 km a week over 12–16 weeks, with long runs of 30–35 km. The key sessions are marathon-pace segments inside long runs and one threshold session a week.
A half marathon around 1:47:55 six to eight weeks before the race is a good checkpoint. If you are slower than 1:51:09, aim for sub 4:00 instead and adjust after your next test.
Weekly volumes are typical ranges, not requirements. Build up gradually and adjust to your own history.
Common questions
How fast is sub 3:45 marathon pace per mile?
8:34 per mile, or 5:19 per kilometre.
What half marathon time do I need for a sub 3:45 marathon?
Around 1:47:55 on Riegel's formula, assuming training that is specific to the marathon.
Should I run even splits?
Yes, or a very slight negative split. Starting faster than goal pace costs far more time late in the race than it gains early. Read how to pace a marathon for a simple plan.
Get the sub 3:45 marathon Race Pace Plan. Tell us your race and goal time. You get one PDF with:
- Goal pace and splits for your race
- Training paces for all five zones
- A printable pace band