Exact distance, exact finish
A half marathon is exactly 21.0975 kilometers, or about 13.1094 miles. The calculator keeps full precision internally, so rounded display pace never changes your finish target.
21.0975 KM · 13.1094 MI
Choose a goal. Get the exact pace, every split, and a race-day plan you can print or share.
Target finish
HALF · 21.1KDisplayed pace is rounded to the nearest second. Every split uses the exact pace.
YOUR RACE PLAN
| Marker | Segment | Target pace | Elapsed |
|---|---|---|---|
| 5 km | 24:53 | 4:59/km | 24:53 |
| 10 km | 24:53 | 4:59/km | 49:46 |
| 15 km | 24:53 | 4:59/km | 1:14:39 |
| 20 km | 24:53 | 4:59/km | 1:39:32 |
| Finish | 5:28 | 4:59/km | 1:45:00 |
QUICK REFERENCE
Choose any finish time to load it into the calculator. Every row uses the exact 21.0975 km distance.
| Finish | Pace /km | Pace /mile | 5K | 10K | Halfway |
|---|---|---|---|---|---|
| 3:19/km | 5:20/mi | 16:35 | 33:11 | 35:00 | |
| 3:33/km | 5:43/mi | 17:46 | 35:33 | 37:30 | |
| 3:48/km | 6:06/mi | 18:58 | 37:55 | 40:00 | |
| 4:02/km | 6:29/mi | 20:09 | 40:17 | 42:30 | |
| 4:16/km | 6:52/mi | 21:20 | 42:40 | 45:00 | |
| 4:30/km | 7:15/mi | 22:31 | 45:02 | 47:30 | |
| 4:44/km | 7:38/mi | 23:42 | 47:24 | 50:00 | |
| 4:59/km | 8:01/mi | 24:53 | 49:46 | 52:30 | |
| 5:13/km | 8:23/mi | 26:04 | 52:08 | 55:00 | |
| 5:27/km | 8:46/mi | 27:15 | 54:31 | 57:30 | |
| 5:41/km | 9:09/mi | 28:26 | 56:53 | 1:00:00 | |
| 5:55/km | 9:32/mi | 29:37 | 59:15 | 1:02:30 | |
| 6:10/km | 9:55/mi | 30:49 | 1:01:37 | 1:05:00 | |
| 6:24/km | 10:18/mi | 32:00 | 1:03:59 | 1:07:30 | |
| 6:38/km | 10:41/mi | 33:11 | 1:06:22 | 1:10:00 | |
| 6:52/km | 11:04/mi | 34:22 | 1:08:44 | 1:12:30 | |
| 7:07/km | 11:27/mi | 35:33 | 1:11:06 | 1:15:00 | |
| 7:21/km | 11:49/mi | 36:44 | 1:13:28 | 1:17:30 | |
| 7:35/km | 12:12/mi | 37:55 | 1:15:50 | 1:20:00 | |
| 7:49/km | 12:35/mi | 39:06 | 1:18:12 | 1:22:30 | |
| 8:03/km | 12:58/mi | 40:17 | 1:20:35 | 1:25:00 | |
| 8:18/km | 13:21/mi | 41:28 | 1:22:57 | 1:27:30 | |
| 8:32/km | 13:44/mi | 42:40 | 1:25:19 | 1:30:00 | |
| 8:46/km | 14:07/mi | 43:51 | 1:27:41 | 1:32:30 | |
| 9:00/km | 14:30/mi | 45:02 | 1:30:03 | 1:35:00 | |
| 9:15/km | 14:52/mi | 46:13 | 1:32:26 | 1:37:30 | |
| 9:29/km | 15:15/mi | 47:24 | 1:34:48 | 1:40:00 | |
| 9:43/km | 15:38/mi | 48:35 | 1:37:10 | 1:42:30 | |
| 9:57/km | 16:01/mi | 49:46 | 1:39:32 | 1:45:00 |
HOW IT WORKS
Enter a finish time or the pace you can hold. The calculator solves the other value using the full half marathon distance.
Stay even, or move a small share of time into the first half to create a continuous negative split.
Use kilometer or mile markers, then share, download, print the full chart, or make a narrow pace band.
A half marathon is exactly 21.0975 kilometers, or about 13.1094 miles. The calculator keeps full precision internally, so rounded display pace never changes your finish target.
Even pacing uses one constant pace. Negative or positive splits use a linear pace curve that satisfies both your chosen halfway clock share and your exact finish time.
A stop buffer reserves clock time for aid stations or brief pauses. It is distributed by distance for planning; your actual stops may happen at different points on the course.
A 2:00:00 half marathon requires an exact average of about 5:41 per kilometer or 9:09 per mile. Use the 2:00 quick goal above to generate every split.
The displayed pace is rounded to a whole second. The split engine keeps the unrounded pace, so its finish time stays exact even when the visible pace is one second higher or lower.
Even splits are the simplest plan. A negative split starts slightly slower and finishes faster. Choose a profile you have practiced and adjust for the real course, conditions, and how you feel on race day.
Yes. Choose “Print pace band” to get a narrow layout with your target, primary pace, and key markers. Your browser can print it or save it as a PDF.