Race Time Prediction
This calculator uses VDOT (VO2max-based training index) developed by Jack Daniels to predict equivalent performances across distances. It assumes proper training for the target distance and similar racing conditions. Predictions are most accurate within similar distance ranges.
Understanding VDOT
VDOT is a running fitness metric that accounts for both speed and endurance. Higher VDOT = better fitness. Recreational: 30-45, Competitive: 45-60, Elite: 60-80. Use VDOT to set training paces and track fitness improvements over time.
Using Predictions
Predictions assume you're trained for the distance. Marathon prediction from 5K requires marathon-specific training (long runs, endurance). Times are goals, not guarantees. Factors affecting actual performance: training volume, course difficulty, weather, pacing strategy, race day nutrition.
Quick Tips
- BMI alone doesn't reflect overall health
- TDEE varies based on activity level
- Consult a healthcare professional for medical decisions
Frequently Asked Questions
No, especially for longer distances. Must train specifically for target distance.
Insufficient training for distance, poor pacing, weather, course difficulty, or nutrition issues.
Most accurate for nearby distances (5K to 10K). Less accurate for big jumps (5K to marathon).
Some runners are naturally better at speed or endurance. Predictions assume balanced training.
Consistent training, interval work, tempo runs, long runs, proper recovery, and gradual mileage increase.