Race Time Predictor
Health & BodyRiegel formula, all distances
Race Time Predictor: Riegel formula, all distances. Race Time Predictor uses standard health formulas to compute accurate results instantly.
Known:10K 25:00(pace 2'30"/km)
Predictions below ↓
| Distance | Riegel | Cameron | Pace needed |
|---|---|---|---|
| 5K | 11:59 | — | 2'24"/km |
| Half | 55:10 | 4:40:55 | 2'37"/km |
| Full | 1:55:00 | 9:21:51 | 2'44"/km |
Formula
- 1Riegel: T₂ = T₁ × (D₂/D₁)^1.06
- 2Cameron (for half/full marathon): accounts for endurance fade, more conservative
- 3Base fitness:
- 410K 25:00 = 2'30"/km
Prediction accuracy notes
| Short → long | Optimistic; needs endurance base |
| Long → short | Fairly reliable |
| Trained runner | ±2-3% error |
| Casual runner | Add 5-10% to predictions |
💡 The 1.06 exponent captures endurance fade — pure speed scaling would use 1.0. Riegel from a recent 10K race is the gold-standard marathon predictor; add 5-10 min if your long runs are under 32km. Cameron tends to be more accurate for marathon from shorter distances.
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How to Use
- Enter body metrics: fill height, weight, age etc. as prompted by the Race Time Predictor.
- Read value and grade: results appear instantly with an authority-based classification.
- Check reference tables: confirm your range and healthy targets against the tables on this page.
- Back-solve your goal: adjust inputs to see what it takes to reach a target.
Key Points
- Race Time Predictor is a free online health tool — open and use, no sign-up.
- All calculations run locally in your browser; your data never leaves the device.
- Key capability: Riegel formula, all distances.
- Results come with formulas and reference tables so you can verify every number.
Formula & How It Works
Race Time Predictor formula
FAQ
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Source & Updates
Based on WHO, ACE, IOM and other published international standards. Last updated: 2025-07
Authoritative sources:
Last updated:
Formulas and content on this page are reviewed by the YiJianSuan team. For reference only — official sources prevail.
Maintained and periodically reviewed by the YiJianSuan editorial team — review process in ourEditorial Policy.
Cite this page: YiJianSuan. Race Time Predictor[EB/OL]. https://www.yijiansuan.com/en/c/health/running-predict
Results provided by this tool are for reference only and do not constitute professional advice.