Estimate FTP from a correctly completed ramp test using the visible 75% convention, or work backward from a target FTP.
How the Ramp Test FTP Calculator Works
A progressive ramp test raises the target power until the rider can no longer continue. A common public estimate sets FTP near 75% of the highest one-minute power achieved during a properly followed test.
The calculator exposes the percentage instead of assuming every platform uses identical processing. It also reverses the formula for riders planning the one-minute result associated with a target FTP.
Formula and Method
Formula: estimated FTP = best one-minute power x protocol fraction
At the default 75%, a 400 W best minute produces a 300 W estimate. The reverse form divides target FTP by 0.75.
Choosing the Right Inputs
Use the best rolling one-minute average from the progressive work portion, not the last displayed step target, a fresh one-minute sprint, or the ride’s overall maximum power.
| Best minute | Factor | Estimated FTP |
|---|---|---|
| 300 W | 75% | 225 W |
| 333 W | 75% | 249.8 W |
| 400 W | 75% | 300 W |
| 400 W | 72% | 288 W |
Understanding Your Results
Estimated FTP or required one-minute power leads, followed by both wattages, the factor, and their difference.
The result is a protocol estimate, not a direct measurement of hour power. Repeatability under similar setup is often more useful than comparing different FTP-test methods.
Worked Example
A best one-minute ramp-test power of 400 W at 75% yields 300 W FTP. Reversing the formula, a 250 W target corresponds to roughly 333 W for the best minute.
Common Mistakes
Do not use a standalone one-minute sprint, treat a partially completed target step as the exact average, or assume a changed factor recreates a platform’s proprietary adjustments.
Assumptions and Limitations
TrainerRoad notes that more complicated calculations may be applied when the power trace does not follow the protocol. Anaerobic contribution, cooling, cadence, trainer mode, and individual physiology can bias the estimate.
Sources
TrainerRoad. FTP Testing – The Cornerstone of Training, current support edition.