Pace Calculator
1:21 Half Marathon Pace
To finish a Half Marathon in 1h21, you need to maintain a pace of 3:50 per km (6:11 per mile). Here's your complete split breakdown.
Pace per KM
3:50
min/km
Pace per Mile
6:11
min/mile
Average Speed
15.6
km/h
1h21 Half Marathon Splits
Plan my Half Marathon pacing strategy →| Distance | Split Pace | Cumulative Time |
|---|---|---|
| 1 km | 3:50 | 3:50 |
| 2 km | 3:50 | 7:41 |
| 3 km | 3:50 | 11:31 |
| 4 km | 3:50 | 15:21 |
| 5 km | 3:50 | 19:12 |
| 6 km | 3:50 | 23:02 |
| 7 km | 3:50 | 26:53 |
| 8 km | 3:50 | 30:43 |
| 9 km | 3:50 | 34:33 |
| 10 km | 3:50 | 38:24 |
| 11 km | 3:50 | 42:14 |
| 12 km | 3:50 | 46:04 |
| 13 km | 3:50 | 49:55 |
| 14 km | 3:50 | 53:45 |
| 15 km | 3:50 | 57:35 |
| 16 km | 3:50 | 1:01:26 |
| 17 km | 3:50 | 1:05:16 |
| 18 km | 3:50 | 1:09:06 |
| 19 km | 3:50 | 1:12:57 |
| 20 km | 3:50 | 1:16:47 |
| 21 km | 3:50 | 1:20:38 |
| 21.10 km | 3:50 | 1:21:00 |
Ready to Run a 1h21 Half Marathon?
Getting to 1h21 for your Half Marathon takes more than just knowing your pace. RunPlan creates a personalized AI training plan based on your current fitness, schedule, and race date to help you hit your goal.