London Marathon 3:45 pace chart
A 3:45:00 finish at the London Marathon averages 8:35 per mile (5:20 per kilometre) — a fast recreational time, roughly the top quintile of a big-city field. Run at even effort rather than even pace, the easiest kilometre comes in around 4:39/km and the hardest around 5:42/km — about 63 seconds between the two extremes. Holding an identical number on every kilometre of a course with this profile means running the climbs too hard and the descents too easy. Held at even effort, halfway comes up at 1:51:56 — a 1:09 positive split, which is what the terrain costs you rather than a pacing error. The hardest kilometre on the course sits near kilometre 20; at this goal time it should take 5:42/km, and giving it that time is the difference between finishing London on plan and unravelling in the last hour.
Kilometre-by-kilometre targets for 3:45:00
Grade-adjusted splits computed from the London Marathon elevation profile with the Minetti gradient-cost model, scaled so the full course adds up to 3:45:00. Uphill sections get more time, downhills less, at one constant effort throughout.
| Kilometre | Target /km | Target /mi | Elev Δ | Elapsed |
|---|---|---|---|---|
| 1 | 5:32 | 8:54 | +22 ft (+7 m) | 5:32 |
| 2 | 5:27 | 8:46 | +13 ft (+4 m) | 10:59 |
| 3 | 5:17 | 8:30 | -7 ft (-2 m) | 16:15 |
| 4 | 5:11 | 8:20 | -20 ft (-6 m) | 21:26 |
| 5 | 4:39 | 7:28 | -86 ft (-26 m) | 26:04 |
| 6 | 5:05 | 8:10 | -31 ft (-9 m) | 31:09 |
| 7 | 5:18 | 8:31 | -6 ft (-2 m) | 36:27 |
| 8 | 5:21 | 8:37 | +2 ft (+1 m) | 41:48 |
| 9 | 5:20 | 8:36 | +1 ft (0 m) | 47:08 |
| 10 | 5:33 | 8:55 | +23 ft (+7 m) | 52:41 |
| 11 | 5:06 | 8:12 | -28 ft (-8 m) | 57:47 |
| 12 | 5:26 | 8:44 | +11 ft (+3 m) | 1:03:12 |
| 13 | 5:13 | 8:24 | -13 ft (-4 m) | 1:08:25 |
| 14 | 5:25 | 8:44 | +10 ft (+3 m) | 1:13:51 |
| 15 | 5:20 | 8:35 | +1 ft (0 m) | 1:19:11 |
| 16 | 5:18 | 8:31 | -4 ft (-1 m) | 1:24:29 |
| 17 | 5:20 | 8:35 | 0 ft (0 m) | 1:29:49 |
| 18 | 5:18 | 8:32 | -4 ft (-1 m) | 1:35:07 |
| 19 | 5:22 | 8:38 | +4 ft (+1 m) | 1:40:29 |
| 20 | 5:14 | 8:25 | -14 ft (-4 m) | 1:45:43 |
| 21 | 5:42 | 9:11 | +38 ft (+12 m) | 1:51:25 |
| 22 | 5:17 | 8:30 | -6 ft (-2 m) | 1:56:41 |
| 23 | 5:14 | 8:25 | -12 ft (-4 m) | 2:01:55 |
| 24 | 5:38 | 9:03 | +26 ft (+8 m) | 2:07:33 |
| 25 | 5:13 | 8:24 | -27 ft (-8 m) | 2:12:46 |
| 26 | 5:12 | 8:22 | -15 ft (-5 m) | 2:17:58 |
| 27 | 5:19 | 8:34 | -2 ft (0 m) | 2:23:17 |
| 28 | 5:38 | 9:04 | +33 ft (+10 m) | 2:28:55 |
| 29 | 5:10 | 8:20 | -20 ft (-6 m) | 2:34:06 |
| 30 | 5:30 | 8:50 | +17 ft (+5 m) | 2:39:35 |
| 31 | 5:28 | 8:48 | -15 ft (-5 m) | 2:45:03 |
| 32 | 5:18 | 8:31 | -5 ft (-1 m) | 2:50:21 |
| 33 | 5:22 | 8:39 | +4 ft (+1 m) | 2:55:44 |
| 34 | 5:26 | 8:44 | +10 ft (+3 m) | 3:01:09 |
| 35 | 5:21 | 8:37 | +1 ft (0 m) | 3:06:30 |
| 36 | 5:25 | 8:43 | +9 ft (+3 m) | 3:11:55 |
| 37 | 5:32 | 8:55 | +23 ft (+7 m) | 3:17:28 |
| 38 | 5:26 | 8:44 | +7 ft (+2 m) | 3:22:53 |
| 39 | 4:54 | 7:53 | -55 ft (-17 m) | 3:27:47 |
| 40 | 5:32 | 8:54 | +20 ft (+6 m) | 3:33:18 |
| 41 | 5:22 | 8:38 | 0 ft (0 m) | 3:38:40 |
| 42 | 5:19 | 8:34 | -3 ft (-1 m) | 3:44:00 |
| 42.2 | 5:09 | 8:18 | -4 ft (-1 m) | 3:45:00 |
Frequently asked questions
What pace is a 3:45 marathon?
A 3:45:00 marathon is 8:35 per mile or 5:20 per kilometre held for the full 26.2 miles (42.195 km). On the London Marathon specifically, the elevation profile means even effort produces uneven splits — the table on this page gives the target for every kilometre.
What should my halfway split be for a 3:45 at the London Marathon?
1:51:56. That is the grade-adjusted halfway target for this course, not simply half of 3:45:00 — it accounts for where the climbing sits. Reaching the half meaningfully faster than this on this course usually means you have spent the effort you need for the closing miles.
Should I run even splits at the London Marathon?
Even effort at a 3:45 goal produces splits between 4:39 and 5:42 per kilometre — about 63 seconds between the easiest and hardest one. Grade-adjusted pacing gives back time on the descents and spends it on the climbs, which is what running an even physiological effort actually looks like on a course with this profile.
How are these London Marathon splits calculated?
Each kilometre is weighted by its gradient using the Minetti et al. (2002) cost-of-running polynomial, which measures the metabolic cost of running at grades from −45% to +45%. The total is then scaled so the whole course adds up to 3:45:00. Uphill sections get more time and downhill sections less, at a constant effort throughout.
Is 3:45 a realistic marathon goal?
3:45 is a fast recreational time, roughly the top quintile of a big-city field. Whether it is realistic for you depends on your recent race results and weekly volume rather than on the number itself — the race-time predictor on this site will convert a recent 5K, 10K or half-marathon result into a marathon estimate using the Riegel power-law model.