Half Marathon Pace Calculator
Calculate your half marathon pace, finish time, and mile-by-mile splits. Enter goal time or current pace to plan your 13.1 mile race strategy.
The half marathon (13.1 miles / 21.1 kilometres) is one of the most popular race distances in the world — demanding enough to require real training, but achievable for runners at all levels. This calculator gives you your required pace, projected finish time, and mile-by-mile splits.
Half Marathon Pace Formula
Pace (min/mile) = Finish time (minutes) ÷ 13.1
Pace (min/km) = Finish time (minutes) ÷ 21.0975
Example — targeting a 2:00:00 (2-hour) half marathon:
- Pace per mile: 120 ÷ 13.1 = 9:10 min/mile
- Pace per km: 120 ÷ 21.0975 = 5:41 min/km
To find finish time from pace:
Finish time = Pace (min/mile) × 13.1
Finish time = Pace (min/km) × 21.0975
Half Marathon Time Benchmarks
| Finish time | Pace (min/mile) | Pace (min/km) | Level |
|---|---|---|---|
| Under 1:05 | 4:58/mile | 3:05/km | Elite |
| 1:05–1:30 | 4:58–6:52/mile | 3:05–4:16/km | Competitive club |
| 1:30–1:45 | 6:52–7:59/mile | 4:16–4:58/km | Strong club runner |
| 1:45–2:00 | 7:59–9:10/mile | 4:58–5:41/km | Solid recreational |
| 2:00–2:20 | 9:10–10:41/mile | 5:41–6:38/km | Average recreational |
| 2:20–3:00 | 10:41–13:44/mile | 6:38–8:32/km | Beginner/run-walk |
Average finish times: Men recreational: 1:55–2:10 | Women recreational: 2:10–2:25
Mile-by-Mile Splits — Key Goal Times
| Mile | 1:45 goal | 2:00 goal | 2:15 goal | 2:30 goal |
|---|---|---|---|---|
| 1 | 8:00 | 9:10 | 10:19 | 11:27 |
| 2 | 16:00 | 18:19 | 20:38 | 22:54 |
| 3 | 24:00 | 27:29 | 30:57 | 34:22 |
| 4 | 32:00 | 36:38 | 41:16 | 45:49 |
| 5 | 40:00 | 45:48 | 51:35 | 57:16 |
| 6 | 48:00 | 54:57 | 61:54 | 68:43 |
| 7 | 56:00 | 64:07 | 72:13 | 80:10 |
| 8 | 64:00 | 73:16 | 82:32 | 91:37 |
| 9 | 72:00 | 82:26 | 92:51 | 103:04 |
| 10 | 80:00 | 91:35 | 103:10 | 114:31 |
| 11 | 88:00 | 100:45 | 113:29 | 125:58 |
| 12 | 96:00 | 109:54 | 123:48 | 137:25 |
| 13 | 104:00 | 119:04 | 134:07 | 148:52 |
| 13.1 | 1:45:00 | 2:00:00 | 2:15:00 | 2:30:00 |
Print your target column and tape it to your wrist or write it on your arm on race day.
Race Day Strategy: Even Splits vs Negative Splits
Even splits (same pace throughout) are achievable for well-trained runners who know their fitness level. Calculate your pace using this calculator and run every mile at that number.
Negative splits (second half faster than first) produce better average times for most runners. Strategy:
- Miles 1–3: Run 10–15 seconds per mile slower than goal pace. Resist the crowd energy.
- Miles 4–9: Settle into goal pace. This should feel controlled, not easy.
- Miles 10–13: If your energy holds, gradually pick up pace.
- Mile 13 to finish: Everything you have left.
Positive splits (going out too fast) cause most bad half marathon races. The energy debt from miles 1–4 can't be repaid and you slow dramatically in the final miles.
Nutrition and Hydration for the Half Marathon
For finishes under 1:45: water at aid stations, no gel needed for most runners.
For 1:45–2:30 finish times:
- Take a gel or chews at miles 4–5 and miles 9–10
- Drink water at every other aid station (every 2–3 miles)
- Practise your fuelling strategy in long training runs — never try something new on race day
For 2:30+ finish times:
- Treat nutrition more like a long training run — gel every 45–60 minutes
- Sports drink at aid stations can replace gel calories
Predicting Half Marathon Time from Other Distances
| 5K time | Predicted half marathon | Marathon prediction |
|---|---|---|
| 22:00 | 1:41:00 | 3:31:00 |
| 25:00 | 1:55:00 | 3:59:00 |
| 28:00 | 2:09:00 | 4:28:00 |
| 32:00 | 2:27:00 | 5:06:00 |
| 36:00 | 2:46:00 | 5:44:00 |
Predictions assume appropriate long-run training for the target distance.
Frequently Asked Questions
What is a good half marathon time for a first-timer?
For a first half marathon, finishing comfortably — regardless of time — is the real goal. Most first-timers finish in 2:00–2:45. Under 2:30 on your first half marathon is a solid result. Many runners set their lifetime PR within the first three or four races as they learn pacing and race-specific fitness.
How do I predict my half marathon time from training runs?
Your half marathon race pace is typically 30–45 seconds per mile faster than your long training run pace (which you run at a conversational pace). If your long runs feel easy at 9:30/mile, your half marathon pace might be around 8:45–9:00/mile. Use recent 5K or 10K race results with the prediction table above for a more accurate forecast.
How long should my longest long run be before a half marathon?
Most training plans peak at 10–12 miles (16–19 km) for the long run, about 2–3 weeks before race day. You don't need to run the full 13.1 miles in training — the race itself provides the extra stimulus, and going longer risks injury close to race day.
What's the hardest mile in a half marathon?
Most runners find miles 9–11 the most difficult — far enough in that early energy is depleted, but not close enough to the finish for the final psychological boost. This is where pacing discipline from the first half pays off. Runners who went out conservatively often find miles 11–13 feel surprisingly manageable.
How many weeks do I need to train for a half marathon?
From a solid 5K base (able to run 5K comfortably without stopping), plan 10–12 weeks of training. From a couch-to-5K level, allow 16–20 weeks. From zero running background, 24 weeks or more.
Related Calculators
- Running Pace Calculator — pace, time, and distance for any run
- Marathon Pace Calculator — scale up to the full 26.2
- 5K Pace Calculator — 5K race pace and finish time
- Heart Rate Zone Calculator — find your training heart rate zones