Calculator input
Example data table
| Example Item | Sample Value | Meaning |
|---|---|---|
| Input method | Race result | Zones are estimated from a recent performance. |
| Race | 10 km in 50:00 | This result estimates a threshold pace near 5:07 per km. |
| Easy zone | About 6:24 to 5:36 per km | Useful for most aerobic mileage and easy days. |
| Tempo zone | About 4:47 to 4:30 per km | Suitable for tempo blocks and sustained quality running. |
| 400 m split view | Shows zone split ranges | Helpful for track sessions and pace checks. |
Formula used
1. Pace from distance and time
Pace = Total Time ÷ Distance
2. Speed from pace
Speed in km/h = 3600 ÷ Seconds per kilometer
3. Threshold pace from race result
The calculator estimates one-hour race pace using a Riegel-style relation:
Estimated 60-minute distance = Race Distance × (3600 ÷ Race Time)1 ÷ 1.06
Threshold Pace per km = 3600 ÷ Estimated 60-minute distance
4. Zone conversion
Each zone is a percentage band of threshold speed. Low and high speeds are converted back into pace ranges.
5. Split calculation
Split Time = Pace per km × Split Distance in km
These are training estimates, not medical or coaching prescriptions.
How to use this calculator
- Choose whether you want to enter a threshold pace or a race result.
- Pick a zone model and your preferred pace display unit.
- Enter your threshold pace, or provide race distance and race time.
- Add a split distance such as 400 meters or 1 kilometer.
- Click the calculate button to place results above the form.
- Review your zone table, threshold pace, speed, and estimated race markers.
- Use the CSV export for spreadsheets or the PDF export for sharing.
- Read the graph to compare how your average speed changes by zone.
FAQs
1. What is a pace zone calculator?
It estimates training pace ranges from a threshold pace or race result. The output helps organize recovery runs, easy days, tempo sessions, and faster interval work.
2. What pace should I enter as threshold pace?
Use a pace you can hold for roughly one hour in a hard, steady effort. Many runners estimate it from a recent 10K, half marathon, or formal threshold test.
3. Why does the calculator offer two zone schemes?
Some runners prefer simpler five-zone guidance. Others want finer seven-zone detail for tempo, steady, interval, and repetition work. Both schemes use the same threshold anchor.
4. Are the race predictions exact?
No. They are rough projections built from threshold pace. Terrain, weather, fatigue, fitness trends, and pacing skill can shift your real race performance up or down.
5. Should I train every day in my highest zone?
No. Most runners improve best by spending the majority of volume in easier zones. Faster zones should support structured workouts, not dominate the full weekly schedule.
6. Why do my split times matter?
Split ranges help you pace repetitions on a track or measured course. They make it easier to match training intent without constantly converting pace in your head.
7. Is pace per mile or pace per kilometer better?
Neither is better universally. Choose the unit you use in training, races, or your watch settings. This calculator also shows the alternate unit for convenience.
8. Can beginners use this calculator?
Yes. Beginners can use it to keep easy days easy and learn pacing control. Start conservatively, especially if your recent race data is limited or outdated.