If you are training for 13.1 miles, pacing is everything. This half marathon pace calculator helps you quickly convert your target finish time into average pace, or convert your preferred pace into a projected finish time. It also gives useful split points so you can race smarter from start to finish.
Interactive Half Marathon Pace Calculator
Half marathon distance is fixed at 13.1094 miles or 21.0975 kilometers.
1) Calculate pace from goal finish time
2) Calculate finish time from target pace
Why half marathon pace matters
Many runners lose time by starting too fast and fading late. A realistic pace plan helps you distribute effort, avoid spikes in heart rate, and finish strong. Whether your goal is to break 2:00, 1:45, or set a new personal best, your average pace gives structure to workouts and confidence on race day.
How to use this calculator
If you know your goal time
Use the first section. Enter your target finish time and click Calculate Pace. You will get:
- Average pace per mile and per kilometer
- Average speed in mph and kph
- Useful checkpoint splits (5K, 10K, 10 miles, etc.)
If you know your target pace
Use the second section. Enter pace in min/mile or min/km and click Calculate Finish Time. This is useful when your training runs suggest a sustainable race rhythm and you want to estimate your finish.
Popular half marathon goals and required pace
| Goal Time | Avg Pace (min/mile) | Avg Pace (min/km) |
|---|---|---|
| 1:30:00 | 6:52 | 4:16 |
| 1:40:00 | 7:38 | 4:44 |
| 1:45:00 | 8:01 | 4:58 |
| 1:50:00 | 8:23 | 5:13 |
| 2:00:00 | 9:09 | 5:41 |
| 2:15:00 | 10:18 | 6:24 |
Training tips to hold pace for 13.1 miles
1. Build aerobic volume first
A consistent base of easy mileage improves endurance and helps you maintain pace when fatigue appears in the final 5K.
2. Add race-specific workouts
Include tempo runs, long runs with fast finishes, and intervals near goal pace. These sessions teach your body and mind how race effort should feel.
3. Practice fueling and hydration
Even in a half marathon, hydration and carbs matter. Practice your race-day strategy during long runs so there are no surprises.
4. Pace with patience
Start controlled for the first 2-3 miles, settle into rhythm, then gradually press if you feel good after mile 10. A slight negative split often beats an aggressive start.
Common pacing mistakes
- Starting too hard: Early excitement can cost minutes late in the race.
- Ignoring weather: Heat, wind, and humidity can require pace adjustments.
- No split checks: Glance at your watch at key markers to stay on track.
- Skipping recovery: Overtraining can make goal pace feel harder than it should.
Final thought
A half marathon pace calculator is simple, but powerful. Use it to set a realistic target, shape your training, and execute your race plan with confidence. Consistency in training plus smart pacing is one of the fastest paths to a stronger 13.1.