Marathon Time Predictor
Predict your 42.195 km marathon finish time from half marathon or 10K times
Input Parameters
Real-time calculation updates dynamically as you adjust inputs. Values remain strictly local on your device.
Predicted Marathon Finish Time5:11 min/km
3:38:55HH:MM:SS
Target pace: 5:11 per km (8.34 min/mile)
Target Speed
11.56km/h
Halfway (21.1K) Split Target
1:45:00HH:MM:SS
Clinical Responsibility Note: This calculation provides statistical estimations for informational and educational purposes only. It is not an individualized medical diagnosis or clinical prescription.
Mathematical Formula & Scientific Methodology
Formula: Riegel Marathon Power Scaling
T(42.2K) = T1 × (42.195 / D1)^1.06Applies the empirical 1.06 fatigue exponent for aerobic capacity across marathon distance.
Model Assumptions
- High weekly training mileage (minimum 50-70 km/week)
- Long runs of 30-34 km completed
- On-course carbohydrate fueling
Variables & Standard Units
| Symbol | Physiological Meaning | Unit |
|---|---|---|
| T1 | Half marathon or 10K race time in seconds | seconds |
| D1 | Benchmark race distance | km |
Scientific Limitations
- Marathon times will be slower than predicted if fueling is neglected or if mileage volume is insufficient to prevent glycogen depletion ('the wall')
Frequently Asked Questions
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