The Cycling Power Race Prediction Calculator estimates a sustainable race power from FTP and expected event duration. It is useful when you know your current threshold power but need a starting point for pacing a time trial, road race, gran fondo segment, or other sustained cycling effort. The model uses a duration-dependent fraction of FTP, so the predicted power gradually falls as the planned effort becomes longer.
The result is best treated as a pacing anchor rather than a promise of race performance. Course profile, drafting, altitude, heat, fueling, fatigue, and how accurately FTP represents current fitness can all move the power you can actually sustain. The calculator also shows the implied intensity factor and estimated work in kilojoules, which helps you compare pacing plans. Start conservatively for unfamiliar events and adjust with experience from similar-duration training sessions.
1. Enter FTP
Use a recent FTP value measured in watts.
2. Set race duration
Enter the expected duration of the sustained race effort in minutes.
3. Read predicted power
The main result is the modelled average power for that duration.
4. Check intensity factor
Compare the predicted power with FTP using the displayed intensity factor.
5. Use as a pacing anchor
Adjust for course demands, conditions, and your own race history rather than chasing the number rigidly.
This is a smooth heuristic duration curve intended for practical pacing estimates. It is not a universal power-duration model and does not account for anaerobic work capacity or course-specific surges.
The predicted wattage is a starting estimate for average sustainable power over the entered duration, assuming FTP is current and the effort is relatively continuous.
Use recent race and training data to calibrate the estimate. Very short, highly stochastic, or draft-heavy events may not fit a single average-power target well.
Given:
FTP = 280 W; expected race duration = 90 min.
Calculation:
Duration = 1.5 h. Intensity factor ≈ 1.03 − 0.055 × ln(4) = 0.954. Predicted power = 280 × 0.954 ≈ 267 W. Work ≈ 267 × 5,400 ÷ 1000 = 1,442 kJ.
Result:
Predicted race power ≈ 267 W.
Interpretation:
A rider with a 280 W FTP could use roughly 267 W as an initial pacing reference for a steady 90-minute effort, then adjust for terrain and race dynamics.
For events near threshold duration, sustainable power can reasonably be close to FTP. The model reduces the fraction as duration becomes longer.
No. It predicts a power target, not speed or finish time, because speed also depends on aerodynamics, gradient, rolling resistance, wind, and drafting.
Use a recent FTP estimate from the same training ecosystem or test method you normally use. An outdated FTP can bias the prediction.
It is less suitable for highly variable events with repeated attacks and coasting. In those races, average power alone does not describe the full demand.
Estimated kilojoules provide a rough measure of mechanical work and can help compare events or fueling plans, but they are not identical to dietary calories burned.