3:45 Marathon Pace
The exact even pace, per-kilometre splits and checkpoint times you need to run a 3:45 marathon — plus fuelling and equivalent race times. Free.
| Distance | Time at even pace |
|---|---|
| 5K | 26:40 |
| 10K | 53:19 |
| 15K | 1:19:59 |
| Half | 1:52:30 |
| 25K | 2:13:19 |
| 30K | 2:39:58 |
| 35K | 3:06:38 |
| 40K | 3:33:18 |
| Finish | 3:45:00 |
⚡ Fuelling for a 3:45 marathon
At roughly 3.8 hours of running, aim for about 60–90 g of carbohydrate per hour (≈ 225–338 g total) and 300–800 mg sodium per hour. Test your exact fuelling in training — never race on something new.
Build your race-day fuel →Full kilometre-by-kilometre split table ▾
| KM | Cumulative | Pace/km |
|---|---|---|
| 1 km | 5:20 | 5:20 |
| 2 km | 10:40 | 5:20 |
| 3 km | 16:00 | 5:20 |
| 4 km | 21:20 | 5:20 |
| 5 km | 26:40 | 5:20 |
| 6 km | 32:00 | 5:20 |
| 7 km | 37:20 | 5:20 |
| 8 km | 42:40 | 5:20 |
| 9 km | 47:59 | 5:20 |
| 10 km | 53:19 | 5:20 |
| 11 km | 58:39 | 5:20 |
| 12 km | 1:03:59 | 5:20 |
| 13 km | 1:09:19 | 5:20 |
| 14 km | 1:14:39 | 5:20 |
| 15 km | 1:19:59 | 5:20 |
| 16 km | 1:25:19 | 5:20 |
| 17 km | 1:30:39 | 5:20 |
| 18 km | 1:35:59 | 5:20 |
| 19 km | 1:41:19 | 5:20 |
| 20 km | 1:46:39 | 5:20 |
| 21 km | 1:51:59 | 5:20 |
| 22 km | 1:57:19 | 5:20 |
| 23 km | 2:02:39 | 5:20 |
| 24 km | 2:07:59 | 5:20 |
| 25 km | 2:13:19 | 5:20 |
| 26 km | 2:18:39 | 5:20 |
| 27 km | 2:23:58 | 5:20 |
| 28 km | 2:29:18 | 5:20 |
| 29 km | 2:34:38 | 5:20 |
| 30 km | 2:39:58 | 5:20 |
| 31 km | 2:45:18 | 5:20 |
| 32 km | 2:50:38 | 5:20 |
| 33 km | 2:55:58 | 5:20 |
| 34 km | 3:01:18 | 5:20 |
| 35 km | 3:06:38 | 5:20 |
| 36 km | 3:11:58 | 5:20 |
| 37 km | 3:17:18 | 5:20 |
| 38 km | 3:22:38 | 5:20 |
| 39 km | 3:27:58 | 5:20 |
| 40 km | 3:33:18 | 5:20 |
| 41 km | 3:38:38 | 5:20 |
| 42 km | 3:43:58 | 5:20 |
| 42.195 km | 3:45:00 | 5:20 |
How to actually run a 3:45 marathon
The pace above assumes an even effort. In a study of over 4 million race records, 28% of men and 17% of women slowed dramatically in the second half — "hitting the wall" — almost always because they banked time early. Aim to reach halfway (1:52:30) on schedule or a few seconds behind, then hold. A flat, even or slight negative split is how most runners hit 3:45.
What pace is a 3:45 marathon?
A 3:45 marathon requires an even pace of 5:20 per kilometre (8:35 per mile), about 11.3 km/h. Over 42.195 km that adds up to exactly 3:45.
What are the 5K, 10K and halfway splits for a 3:45 marathon?
At even pace you pass 5K in 26:40, 10K in 53:19, and the halfway point (21.1 km) in 1:52:30. Reaching halfway meaningfully faster than 1:52:30 is the classic positive-split mistake that causes late-race slowdown.
How many carbohydrates do I need for a 3:45 marathon?
For a run of about 3.8 hours, sports-nutrition consensus is roughly 60–90 g of carbohydrate per hour — around 225–338 g total — plus 300–800 mg of sodium per hour depending on sweat rate. Practise your exact fuelling in training; never try anything new on race day.
Times are mathematical even-pace targets, not a guarantee. Real results vary with course, weather, fitness and fuelling. Nutrition guidance is general — consult a professional for individual needs.