1:20 Half MarathonPace Chart & Split Guide
Pace chart for a 1:20 half marathon with mile and kilometer splits, plus modelled 5K and 10K race equivalents.
1:20 Half Marathon
Pace/km
3:48
Pace/mi
6:06
Distance
21.1km
Avg Speed
15.8km/h
Kilometer Splits
| KM | Split | Elapsed |
|---|---|---|
| 1 | 3:48 | 3:48 |
| 2 | 3:48 | 7:35 |
| 3 | 3:48 | 11:23 |
| 4 | 3:48 | 15:10 |
| 5 | 3:48 | 18:58 |
| 6 | 3:48 | 22:45 |
| 7 | 3:48 | 26:33 |
| 8 | 3:48 | 30:20 |
| 9 | 3:48 | 34:08 |
| 10 | 3:48 | 37:55 |
| 11 | 3:48 | 41:43 |
| 12 | 3:48 | 45:30 |
| 13 | 3:48 | 49:18 |
| 14 | 3:48 | 53:05 |
| 15 | 3:48 | 56:53 |
| 16 | 3:48 | 1:00:40 |
| 17 | 3:48 | 1:04:28 |
| 18 | 3:48 | 1:08:15 |
| 19 | 3:48 | 1:12:03 |
| 20 | 3:48 | 1:15:50 |
| 21 | 3:48 | 1:19:38 |
| 21.10Finish | 0:22 | 1:20:00 |
Mile Splits
| Mile | Split | Elapsed |
|---|---|---|
| 1 | 6:06 | 6:06 |
| 2 | 6:06 | 12:12 |
| 3 | 6:06 | 18:18 |
| 4 | 6:06 | 24:25 |
| 5 | 6:06 | 30:31 |
| 6 | 6:06 | 36:37 |
| 7 | 6:06 | 42:43 |
| 8 | 6:06 | 48:49 |
| 9 | 6:06 | 54:55 |
| 10 | 6:06 | 1:01:02 |
| 11 | 6:06 | 1:07:08 |
| 12 | 6:06 | 1:13:14 |
| 13 | 6:06 | 1:19:20 |
| 13.11Finish | 0:40 | 1:20:00 |
Modelled race equivalents for a 1:20 half marathon
If this result represents current race fitness, the standard Riegel model (k=1.06) estimates the comparison times below. They are model outputs, not guaranteed performances; terrain, conditions, pacing, fueling, and distance-specific preparation still matter.
5K
17:23
10K
36:15
Marathon
2:46:48
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Pacing Notes for Your 1:20 Half Marathon
Half Marathon Pace Considerations
- Use the split table to rehearse pacing, then adjust it for course and weather.
- Only use fueling and equipment that you have already tested in training.
- Check effort as well as pace; GPS and terrain can distort individual splits.
- A goal time alone cannot determine safe weekly mileage or workout volume.
Race Execution Prompts
Mindset
Treat the goal as a pacing hypothesis and respond to conditions and effort.
Pacing
Start controlled, monitor average pace over stable segments, and adjust rather than forcing a failing plan.
Frequently Asked Questions
What pace do I need to run a 1:20 half marathon?
The mathematical average is 3:48 per kilometer or 6:06 per mile. Course distance, GPS error, hills, wind, and aid-station time can change the pace you see on race day.
Does a 1:20 goal determine my training plan?
No. Goal time alone cannot determine safe mileage, workout volume, or recovery. Use current training history and recent performance with a qualified coach or an established plan.
Does this page prescribe nutrition or gear?
No. Fuel, hydration, footwear, and equipment are individual decisions that should be tested in training; this page calculates pacing and splits only.
What 5K and 10K times are equivalent to a 1:20 half marathon?
Using the standard Riegel model with k=1.06, the comparison times are 17:23 for 5K and 36:15 for 10K. These are modelled scenarios, not guarantees of race performance.
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