FTP Calculator
Calculate Functional Threshold Power from a 20-min, 8-min, or ramp test
Inputs
A solo, all-out 20-min effort with a proper warm-up. Take the average watts for the full 20 minutes.
Estimated FTP
250W
Based on your 20-minute test (FTP ≈ 95% × 20-min average).
Treat this as a starting point. Re-test every 6–8 weeks during build phases; FTP shifts with training state.
How these numbers come from
20-minute test (Allen & Coggan) — the most-used field protocol. After a 20-min all-out effort, take 95% of the average power. Source: Allen & Coggan, Training and Racing with a Power Meter (3rd ed., 2019).
8-minute test (Carmichael / CTS) — two all-out 8-minute efforts, 10 min easy between. FTP ≈ 90% of the average of the two. Slightly more anaerobic-influenced than the 20-min test; useful for athletes who can't sustain a clean 20-min effort.
Ramp test — a graded test (+25 W/min or +20 W/min) until failure. MAP = the 1-min peak. FTP ≈ 75% of MAP. Reference: Mackinnon & Hooper (1991) for the ramp protocol; the 75% factor is empirical.
None of these protocols give you the same number to the watt. Differences of ±5% are normal. The "right" FTP is whichever one you can hold for an hour at a real, race-pace effort.
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