Cycling FTP Calculator
The One Number That Sets Every Training Zone
Functional Threshold Power — the highest power output a cyclist can sustain for roughly an hour — is the single reference figure that structured cycling training is built around. Every zone, from easy recovery spins to short maximal efforts, is defined as a percentage of FTP. Get the FTP number wrong and every zone built from it is wrong too, which is why the test protocol used to establish it matters.
The Formulas
This calculator supports the two most common field-test protocols:
Ramp Test: FTP = Best 1-Minute Average Power (final completed stage) × 0.75
The 20-minute test applies a 0.95 correction factor because a rider can sustain slightly higher power for 20 minutes than for a full hour. The ramp test estimates FTP from the highest one-minute power a rider can sustain during an incrementally increasing-effort protocol, scaled down by 0.75 to approximate sustainable hour-long power from a short maximal effort.
Where This Calculation Matters
- Structuring interval workouts — every zone from recovery to neuromuscular power is defined as a percentage range of FTP, so a workout prescribed as "Zone 4 intervals" only means something concrete once FTP is known.
- Tracking fitness gains — retesting FTP periodically through a training block is the standard way to confirm that training is producing a real power increase, not just a subjective feeling of getting fitter.
- Race pacing — time trial and climbing pacing strategies are commonly planned as a percentage of FTP to avoid starting too hard and fading.
- Cross-referencing power-to-weight — FTP divided by body weight gives the W/kg figure used to classify climbing ability and competitive category.
Power Zones at an Example FTP
Computed directly from the calculator's own zone table, based on a 20-minute test average power of 263W (FTP = 263 × 0.95 = 249.8W):
| Zone | % of FTP | Power range |
|---|---|---|
| Zone 1 – Active Recovery | 0–55% | 0–137 W |
| Zone 2 – Endurance | 55–75% | 137–187 W |
| Zone 3 – Tempo | 75–90% | 187–225 W |
| Zone 4 – Lactate Threshold | 90–105% | 225–262 W |
| Zone 5 – VO2 Max | 105–120% | 262–300 W |
| Zone 6 – Anaerobic Capacity | 120–150% | 300–375 W |
| Zone 7 – Neuromuscular Power | 150%+ | 375+ W |
How to Use This Calculator
- Select the test protocol — 20-Minute Test or Ramp Test.
- Enter the corresponding power figure: 20-minute average power, or best 1-minute average power from the final completed stage.
- Select Calculate to see your estimated FTP and full seven-zone power training breakdown.
Related Calculations
To convert FTP into a power-to-weight ratio, see the Cycling Power-to-Weight Ratio Calculator. For average ride speed rather than sustained power, check the Cycling Speed Calculator.