1:20 Half Marathon Pace: 6:06/mi (3:48/km)
A 1:20 half marathon is 6:06 per mile, or 3:48 per kilometer, held for 13.1 miles (21.0975 km). Halfway comes at 40:00. Below: splits for three pacing strategies, what your recent races say about this goal, and a plan built for it.
1:20 half marathon splits: even, negative and positive
Even pacing holds the same pace from the first mile to the last. A negative split runs the first half at 51 % of the goal time and the second half at 49 %, so you finish faster than you started. A positive split (49/51) banks a small cushion early and gives it back later; it is the most common way to run a race and the hardest way to run it well. The finish time is the same in all three columns, only the cumulative time at each mark changes.
| Mile | Even | Negative split 51/49 | Positive split 49/51 |
|---|---|---|---|
| 1 | 6:06 | 6:13 | 5:59 |
| 2 | 12:12 | 12:27 | 11:58 |
| 3 | 18:18 | 18:40 | 17:56 |
| 4 | 24:25 | 24:54 | 23:55 |
| 5 | 30:31 | 31:07 | 29:54 |
| 6 | 36:37 | 37:21 | 35:53 |
| Half | 40:00 | 40:48 | 39:12 |
| 7 | 42:43 | 43:28 | 41:58 |
| 8 | 48:49 | 49:27 | 48:12 |
| 9 | 54:55 | 55:25 | 54:25 |
| 10 | 1:01:02 | 1:01:24 | 1:00:39 |
| 11 | 1:07:08 | 1:07:23 | 1:06:52 |
| 12 | 1:13:14 | 1:13:22 | 1:13:06 |
| 13 | 1:19:20 | 1:19:21 | 1:19:19 |
| Finish | 1:20:00 | 1:20:00 | 1:20:00 |
| Km | Even | Negative split 51/49 | Positive split 49/51 |
|---|---|---|---|
| 1 | 3:48 | 3:52 | 3:43 |
| 2 | 7:35 | 7:44 | 7:26 |
| 3 | 11:23 | 11:36 | 11:09 |
| 4 | 15:10 | 15:28 | 14:52 |
| 5 | 18:58 | 19:20 | 18:35 |
| 6 | 22:45 | 23:12 | 22:18 |
| 7 | 26:33 | 27:04 | 26:01 |
| 8 | 30:20 | 30:57 | 29:44 |
| 9 | 34:08 | 34:49 | 33:27 |
| 10 | 37:55 | 38:41 | 37:10 |
| Half | 40:00 | 40:48 | 39:12 |
| 11 | 41:43 | 42:29 | 40:57 |
| 12 | 45:30 | 46:12 | 44:49 |
| 13 | 49:18 | 49:55 | 48:41 |
| 14 | 53:05 | 53:38 | 52:33 |
| 15 | 56:53 | 57:20 | 56:25 |
| 16 | 1:00:40 | 1:01:03 | 1:00:17 |
| 17 | 1:04:28 | 1:04:46 | 1:04:09 |
| 18 | 1:08:15 | 1:08:29 | 1:08:01 |
| 19 | 1:12:03 | 1:12:12 | 1:11:53 |
| 20 | 1:15:50 | 1:15:55 | 1:15:45 |
| 21 | 1:19:38 | 1:19:38 | 1:19:37 |
| Finish | 1:20:00 | 1:20:00 | 1:20:00 |
Are you ready for a 1:20 half marathon?
The Riegel formula (T2 = T1 × (D2 ÷ D1)1.06) links race times across distances. Recent results around these mark you as fit for a half marathon in 1:20:
| Recent race | Time that predicts 1:20 | Pace |
|---|---|---|
| Marathon | 2:46:48 | 6:22/mi · 3:57/km |
| 10K | 36:15 | 5:50/mi · 3:38/km |
| 5K | 17:23 | 5:36/mi · 3:29/km |
The shorter the reference race, the more the prediction depends on your endurance training; a recent result at a neighbouring distance is the most reliable guide.
Check your own numbers in the pace calculator, or let the generator use a recent race for training paces.
Build a free 1:20 half marathon plan
Same engine as every plan on this site, but with your race date, your run days and your longest recent run. Prints to PDF, exports to your calendar. No signup.
Frequently asked questions
What pace is a 1:20 half marathon?
6:06 per mile, or 3:48 per kilometer, for the full 13.1 miles. Running even splits you pass halfway at 40:00.
What is the halfway split for a 1:20 half marathon?
40:00 with even pacing, 40:48 with a negative split (51/49), 39:12 with a positive split (49/51).
What Marathon, 10K, 5K time predicts a 1:20 half marathon?
Marathon in about 2:46:48, 10K in about 36:15, 5K in about 17:23 (Riegel formula, exponent 1.06).
How many weeks do I need to train for a 1:20 half marathon?
The generator builds half marathon plans from 8 to 24 weeks and defaults to 12; it counts back from your race date. Enter 1:20 as the goal time and the plan sets easy, long and tempo paces from it.
Should I run a 1:20 half marathon with even or negative splits?
Even or slightly negative. Both start conservatively; a negative split means your second half is faster, which is how most personal bests are run. A positive split spends energy early and is the usual cause of a slow last quarter.