Sub 3:45 marathon pace

Q: What pace do I need for Sub 3:45 marathon pace?

To run 3:45:00 for a Marathon, you need to average 5:20 per km (8:35 per mile), or 11.3 km/h.

Q: How do I pace a Marathon at 3:45:00?

For even splits, run every kilometre at 5:20. For negative splits, start at slightly slower than 5:20 and gradually increase pace through the second half. Never go out faster than goal pace in the first km.

Goal time

3:45:00

Pace / km

5:20

Pace / mile

8:35

Speed

11.3 km/h

Even splits — 3:45:00 Marathon

km	Pace	Cumulative
1	5:20	0:05:20
2	5:20	0:10:40
3	5:20	0:15:60
4	5:20	0:21:20
5	5:20	0:26:40
6	5:20	0:31:60
7	5:20	0:37:20
8	5:20	0:42:40
9	5:20	0:47:59
10	5:20	0:53:19
11	5:20	0:58:39
12	5:20	1:03:59
13	5:20	1:09:19
14	5:20	1:14:39
15	5:20	1:19:59
16	5:20	1:25:19
17	5:20	1:30:39
18	5:20	1:35:59
19	5:20	1:41:19
20	5:20	1:46:39
21	5:20	1:51:59
22	5:20	1:57:19
23	5:20	2:02:39
24	5:20	2:07:59
25	5:20	2:13:19
26	5:20	2:18:39
27	5:20	2:23:58
28	5:20	2:29:18
29	5:20	2:34:38
30	5:20	2:39:58
31	5:20	2:45:18
32	5:20	2:50:38
33	5:20	2:55:58
34	5:20	3:01:18
35	5:20	3:06:38
36	5:20	3:11:58
37	5:20	3:17:18
38	5:20	3:22:38
39	5:20	3:27:58
40	5:20	3:33:18
41	5:20	3:38:38
42	5:20	3:43:58
43	5:20	3:45:00

Negative splits (3% variance)

km	Pace	Cumulative
1	5:29	0:05:29
2	5:29	0:10:58
3	5:28	0:16:27
4	5:28	0:21:55
5	5:27	0:27:22
6	5:27	0:32:49
7	5:27	0:38:16
8	5:26	0:43:42
9	5:26	0:49:07
10	5:25	0:54:33
11	5:25	0:59:57
12	5:24	1:05:22
13	5:24	1:10:46
14	5:23	1:16:09
15	5:23	1:21:32
16	5:22	1:26:54
17	5:22	1:32:16
18	5:22	1:37:38
19	5:21	1:42:59
20	5:21	1:48:20
21	5:20	1:53:40
22	5:20	1:58:60
23	5:19	2:04:19
24	5:19	2:09:38
25	5:18	2:14:56
26	5:18	2:20:14
27	5:17	2:25:32
28	5:17	2:30:49
29	5:17	2:36:05
30	5:16	2:41:22
31	5:16	2:46:37
32	5:15	2:51:52
33	5:15	2:57:07
34	5:14	3:02:21
35	5:14	3:07:35
36	5:13	3:12:49
37	5:13	3:18:02
38	5:12	3:23:14
39	5:12	3:28:26
40	5:12	3:33:38
41	5:11	3:38:49
42	5:11	3:43:59
43	5:10	3:44:60

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How to run Sub 3:45 marathon pace

Running 3:45:00 for a Marathon requires averaging exactly 5:20 per kilometre from start to finish. This equates to 8:35 per mile, or 11.3 km/h. Even a small deviation from goal pace early in the race has a compounding effect — going 10 seconds per km too fast in the first 5 km costs significantly more than those 10 seconds by the finish.

The most reliable strategy is to run the first kilometre at 5:26 — about 2% slower than goal pace — and gradually increase through the second half. This negative split approach preserves glycogen and keeps your heart rate below threshold until you need it.

Print the even splits table above or load it on your watch before the race. Having per-kilometre splits written on your arm or programmed into your GPS watch removes all guesswork and lets you execute the race without mental arithmetic.

Frequently asked questions

What pace do I need for Sub 3:45 marathon pace?

You need to average 5:20 per km (8:35 per mile) — equivalent to 11.3 km/h throughout the entire Marathon.

How do I pace a Marathon at 3:45:00?

For even splits, run every km at 5:20. For a safer negative split, start the first km at 5:26 and gradually quicken through the second half. Never start faster than goal pace.