FTP / Power Zone Calculator
Calculate your Functional Threshold Power and cycling training zones from a test result.
Average wattage from a 20-minute all-out effort
Your Estimated FTP
200W × 0.95 = 190W
Your Power Zones
Race Pacing Guidelines
Frequently Asked Questions
How do I calculate my FTP from a 20-minute test?
Take your average power over a maximal 20-minute effort and multiply it by 0.95. The calculator above does this automatically and also converts the result into training zones and race-day power targets.
What power should I ride at in an Ironman?
Most athletes ride an Ironman bike leg at 65–70% of FTP, a 70.3 at 70–75%, an Olympic at 75–85% and a sprint at 85–95%. Riding above these ranges is the most common cause of a slow, walked marathon.
What is a good FTP for a triathlete?
Judge FTP relative to body weight, not in raw watts. Beginners typically sit at 2.0–2.5 W/kg, solid age-groupers at 3.0–3.5 W/kg, and competitive long-course athletes at 4.0 W/kg or above.
How often should I retest my FTP?
Every 6–8 weeks during a structured build. Testing more often adds fatigue without meaningful new data, and testing less often means you spend weeks training with zones that are too easy.
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