Running pace calculator
Distance and time in, pace out — per kilometre, per mile and in km/h. And the reverse: pick a pace and see what it finishes in. Everything runs in your browser and nothing is sent anywhere.
5:41MIN /KM
The single most useful pace in amateur running: a two-hour half marathon and a four-hour marathon are the same number. If 5:41 is the limit you can just about hold for 21 km, sub-4 for the marathon is not a goal yet.
COMPUTED·7,200 s ÷ 21.0975 km = 14,400 s ÷ 42.195 km·NOT AN ESTIMATE, NOT A MODEL·WORKING CHECKED JUL 2026
Enter a distance and a time.
The one division everything here rests on
- Take the target off the stub and turn it into seconds. Two hours is 7,200.
- Divide by the official distance in kilometres — 21.0975 for the half, 42.195 for the marathon, never the rounded ones. That quotient is the pace you have to hold, in seconds per kilometre.
- Multiply that pace by each kilometre mark in turn. Those products are the cumulative clock readings printed against the ticks — the numbers you compare your watch to, rather than dividing under fatigue.
- Convert once for the units you race in: ×1.609344 for a mile, 3,600 ÷ pace for km/h.
- Scale the splits so they sum to the target exactly, so no rounding drift accumulates across 42 ticks.
pace/km = target seconds ÷ distance km split(k) = pace/km × k (k = 1 … n, cumulative) halfway = target seconds ÷ 2 pace/mile = pace/km × 1.609344 km/h = 3600 ÷ pace/km
The other direction — pick a pace, see the finish time
The question most runners actually have before a race: if I can hold this, what do I finish in?
Enter a distance and a pace.
Pace chart — every pace against every race distance
The complete table, rendered on the server. Find your pace on the left and read across; find your target time in a column and read back to the pace you need. Distances are the official ones: 21.0975 km for the half and 42.195 km for the marathon.
| Pace /km | Pace /mile | km/h | 5K | 10K | Half | Marathon |
|---|---|---|---|---|---|---|
| 3:00 | 4:50 | 20.0 | 15:00 | 30:00 | 1:03:18 | 2:06:35 |
| 3:10 | 5:06 | 18.9 | 15:50 | 31:40 | 1:06:49 | 2:13:37 |
| 3:20 | 5:22 | 18.0 | 16:40 | 33:20 | 1:10:20 | 2:20:39 |
| 3:30 | 5:38 | 17.1 | 17:30 | 35:00 | 1:13:50 | 2:27:41 |
| 3:40 | 5:54 | 16.4 | 18:20 | 36:40 | 1:17:21 | 2:34:43 |
| 3:50 | 6:10 | 15.7 | 19:10 | 38:20 | 1:20:52 | 2:41:45 |
| 4:00 | 6:26 | 15.0 | 20:00 | 40:00 | 1:24:23 | 2:48:47 |
| 4:10 | 6:42 | 14.4 | 20:50 | 41:40 | 1:27:54 | 2:55:49 |
| 4:20 | 6:58 | 13.8 | 21:40 | 43:20 | 1:31:25 | 3:02:51 |
| 4:30 | 7:15 | 13.3 | 22:30 | 45:00 | 1:34:56 | 3:09:53 |
| 4:40 | 7:31 | 12.9 | 23:20 | 46:40 | 1:38:27 | 3:16:55 |
| 4:50 | 7:47 | 12.4 | 24:10 | 48:20 | 1:41:58 | 3:23:57 |
| 5:00 | 8:03 | 12.0 | 25:00 | 50:00 | 1:45:29 | 3:30:59 |
| 5:10 | 8:19 | 11.6 | 25:50 | 51:40 | 1:49:00 | 3:38:00 |
| 5:20 | 8:35 | 11.3 | 26:40 | 53:20 | 1:52:31 | 3:45:02 |
| 5:30 | 8:51 | 10.9 | 27:30 | 55:00 | 1:56:02 | 3:52:04 |
| 5:40 | 9:07 | 10.6 | 28:20 | 56:40 | 1:59:33 | 3:59:06 |
| 5:50 | 9:23 | 10.3 | 29:10 | 58:20 | 2:03:04 | 4:06:08 |
| 6:00 | 9:39 | 10.0 | 30:00 | 1:00:00 | 2:06:35 | 4:13:10 |
| 6:10 | 9:55 | 9.7 | 30:50 | 1:01:40 | 2:10:06 | 4:20:12 |
| 6:20 | 10:12 | 9.5 | 31:40 | 1:03:20 | 2:13:37 | 4:27:14 |
| 6:30 | 10:28 | 9.2 | 32:30 | 1:05:00 | 2:17:08 | 4:34:16 |
| 6:40 | 10:44 | 9.0 | 33:20 | 1:06:40 | 2:20:39 | 4:41:18 |
| 6:50 | 11:00 | 8.8 | 34:10 | 1:08:20 | 2:24:10 | 4:48:20 |
| 7:00 | 11:16 | 8.6 | 35:00 | 1:10:00 | 2:27:41 | 4:55:22 |
| 7:10 | 11:32 | 8.4 | 35:50 | 1:11:40 | 2:31:12 | 5:02:24 |
| 7:20 | 11:48 | 8.2 | 36:40 | 1:13:20 | 2:34:43 | 5:09:26 |
| 7:30 | 12:04 | 8.0 | 37:30 | 1:15:00 | 2:38:14 | 5:16:28 |
| 7:40 | 12:20 | 7.8 | 38:20 | 1:16:40 | 2:41:45 | 5:23:30 |
| 7:50 | 12:36 | 7.7 | 39:10 | 1:18:20 | 2:45:16 | 5:30:32 |
| 8:00 | 12:52 | 7.5 | 40:00 | 1:20:00 | 2:48:47 | 5:37:34 |
COMPUTED·pace × official distance, for all four race distances·NOT AN ESTIMATE, NOT A MODEL·WORKING CHECKED JUL 2026
Full-resolution charts in 5-second steps, one per distance: 5K, 10K, half marathon, marathon.
How the arithmetic works
Pace is time divided by distance, and everything else on this page is a unit conversion of that one division. Time in seconds ÷ distance in kilometres gives seconds per kilometre; multiply by 1.609344 for seconds per mile; divide 3,600 by it for kilometres per hour. There is no model, no fitness assumption and nothing to calibrate.
The reason a pace calculator is worth having anyway is that races are decided by arithmetic done badly under stress. At 18 km of a half marathon, working out whether 5:44 for the last three kilometres still gets you under two hours is not a calculation anybody does well. Doing it at your kitchen table the night before, and writing the cumulative splits on your arm, is the entire trick — which is what the split calculator prints.
Two pace equivalences worth memorising
5:41 per kilometre is simultaneously a two-hour half marathon and a four-hour marathon. 4:58 per kilometre is a 1:45 half and a 3:30 marathon. Those pairs are exact, not approximate, because the marathon is exactly twice the half. They are the fastest way to check whether a marathon goal is realistic: the marathon version of a pace you can only just hold for 21 km is not a goal, it is a plan to walk from 30 km.
What the arithmetic cannot tell you is whether you can hold the pace. For that, put a recent race into the finish-time predictor, which applies Riegel's endurance formula, or the VO2max estimator.
Questions from the start line
How do I calculate running pace?
Divide your total time in seconds by the distance in kilometres. 55 minutes for 10 km is 3,300 seconds ÷ 10 = 330 seconds per kilometre, which is 5 minutes 30 seconds per kilometre. Nothing on this page does anything more complicated than that.
What pace is a 2 hour half marathon?
5:41 per kilometre. Two hours is 7,200 seconds and the half marathon is 21.0975 km, so 7,200 ÷ 21.0975 = 341.3 seconds per kilometre. Most runners target 5:37 to leave a margin for water stops and a crowded start.
What pace is a 4 hour marathon?
5:41 per kilometre — exactly the same pace as a 2 hour half marathon, held for twice as long. That equivalence is the most useful sanity check in amateur running: if 5:41 is your limit for 21 km, sub-4 for the marathon is not yet realistic.
How do I convert pace per km to pace per mile?
Multiply by 1.609344. A 5:00 per kilometre pace is 5 × 60 = 300 seconds, and 300 × 1.609344 = 483 seconds, which is 8:03 per mile.
What speed on a treadmill is a given pace?
Speed in km/h is 3,600 divided by your pace in seconds per kilometre. 5:00 per km is 300 seconds, so 3,600 ÷ 300 = 12.0 km/h. The treadmill converter on this site does the same sum both ways.
Every time, pace and physiological figure on this site is computed from a published formula, and the formula is named and shown on the method page. Nothing here is predicted by a model you cannot check. Race details change — always confirm dates, routes and entry with the official organiser. Training guidance is general information, not individual coaching or medical advice.
ਸਰੋਤ·Race calendars + pace computation·ਸਮੀਖਿਆ ਜੁਲਾਈ 2026
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