The Best Free Power Zone Calculator (and How to Use It)
Enter your FTP and get all seven cycling power zones in watts, free, no email or account. How the calculator works and how to estimate FTP inside it.
A power zone calculator turns one number, your FTP (functional threshold power), into the watts ranges you train in. Enter your FTP and ours lays out all seven Coggan power zones in watts, with what each trains and how it feels. Free, works on your phone, no email or account. Below: how to use it, what to do if you do not know your FTP, and why it is the best free power zone calculator (also searched as "powerzone calculator").
What a power zone calculator does
Every zone is a slice of your FTP. Zone 2 endurance is 56–75% of FTP, threshold is 91–105%, and so on up to sprints. The calculator does the maths the instant you type your FTP and redoes it when the number changes.
It uses the Coggan 7-zone model, the standard TrainingPeaks, Zwift, Garmin and Wahoo build on, so the ranges match your head unit and platform. It also marks sweet spot (88–94% of FTP), the band just below threshold that structured plans lean on. For what each zone develops, see the Coggan power zones.
How to use it
- Enter your FTP in watts.
- Read your zones. All seven bands appear in watts, labelled with what they train and how they feel.
- Adjust and compare. Change the number and everything recalculates, so you can see how a 10-watt FTP gain shifts every zone.
FTP
250W
Sweet Spot
220–235W
88–94% FTP
| Zone | Bereik | Wat het traint |
|---|---|---|
| Z1 | Actief Herstel ≤ 138 W | Herstel; laat de benen draaien zonder belasting toe te voegen. RPE 1–2, heel makkelijk. |
| Z2 | Duurvermogen 139–188 W | Aerobe basis, vetverbranding, de hele dag vol te houden tempo. RPE 3–4, pratend. |
| Z3 | Tempo 189–225 W | Aeroob duurvermogen en spierefficiëntie. RPE 5–6, comfortabel zwaar. |
| Z4 | Drempel 226–263 W | Lactaatdrempel, FTP-werk, het houdbare plafond. RPE 7–8, herhalingen van 10–30 min. |
| Z5 | VO₂max 264–300 W | Maximaal aeroob vermogen; intervallen van 3–8 min. RPE 9, heel zwaar. |
| Z6 | Anaerobe Capaciteit 301–375 W | Anaerobe capaciteit; inspanningen van 30s–3min. RPE 9–10, bijna maximaal. |
| Z7 | Neuromusculair Vermogen ≥ 376 W | Sprint- en neuromusculair vermogen. RPE 10, voluit gesprint. |
Z1 · Actief Herstel. Herstel; laat de benen draaien zonder belasting toe te voegen. RPE 1–2, heel makkelijk.
Z2 · Duurvermogen. Aerobe basis, vetverbranding, de hele dag vol te houden tempo. RPE 3–4, pratend.
Z3 · Tempo. Aeroob duurvermogen en spierefficiëntie. RPE 5–6, comfortabel zwaar.
Z4 · Drempel. Lactaatdrempel, FTP-werk, het houdbare plafond. RPE 7–8, herhalingen van 10–30 min.
Z5 · VO₂max. Maximaal aeroob vermogen; intervallen van 3–8 min. RPE 9, heel zwaar.
Z6 · Anaerobe Capaciteit. Anaerobe capaciteit; inspanningen van 30s–3min. RPE 9–10, bijna maximaal.
Z7 · Neuromusculair Vermogen. Sprint- en neuromusculair vermogen. RPE 10, voluit gesprint.
- Andrew Coggans zevenzonemodel drukt elke zone uit als een percentage van Functional Threshold Power. De Sweet Spot (220–235 W, 88–94% FTP) ligt tussen Tempo en Drempel en geeft een hoge trainingsprikkel bij matige vermoeidheid.
- FTP is het vermogen dat je theoretisch ongeveer een uur zou kunnen volhouden. Hertest elke 4–6 weken; een verouderde FTP maakt elke zone verkeerd.
Een PDF met je resultaten, plus een QR-code om ze altijd opnieuw te openen.
Come back to the FTP calculator whenever you retest.
Don't know your FTP? Estimate it here
The same tool estimates FTP from a short maximal effort. Pick the test and it applies the standard factor:
- 20-minute test: FTP = 95% of your best 20-minute average power. The classic field test.
- 8-minute test: FTP = 90% of your best 8-minute power. Shorter and friendlier.
- Ramp test: FTP ≈ 75% of your 1-minute peak (MAP) at the end of a ramp. Least dependent on pacing.
Drop the number in and you get FTP and zones together. For choosing and pacing a test, read what's a good FTP.
Why it's the best free power zone calculator
- More than one model. Most calculators only do Coggan FTP zones. We also have Critical Power, which fits CP and W′ from a couple of efforts, and Stryd-style running power zones.
- Open, tested maths. Every formula is implemented from its primary source and unit-tested against published reference values. See methodology.
- Free and private. No email wall, no account, no upsell. Your FTP never leaves your device.
- Fast and mobile-first. Built to use on a phone next to a turbo trainer.
Keep a record of your zones
Hit Download to save a PDF of your zone chart. It matches the screen and carries a QR code back to the calculator, so you can:
- Pin it above your trainer or tape it to your stem.
- Keep a dated record each time you retest and watch FTP climb over a season.
- Re-open the calculator from the QR code after your next test.
Nothing is stored on our end. You keep the record. Retest every 4–8 weeks of focused training and save a fresh one.
Power zones, heart-rate zones, or pace?
Power is what you produce: instant and unaffected by heat, sleep or caffeine. Heart rate is how your body responds. It lags and drifts, which is why a 5-second sprint barely moves it. Without a power meter, use heart-rate zones or, for running, pace zones. Many riders watch power for the effort and heart rate for fatigue. The "mostly easy, a little very hard" shape is what the polarized model prescribes.
Accuracy: garbage in, garbage out
The calculator is only as good as the FTP you feed it. A guessed or months-old FTP gives confident but wrong zones, because every band shifts with it. Test honestly, retest every 4–8 weeks while training hard, and treat the boundaries as overlapping guidelines rather than walls (Coggan stresses this himself).
FAQ
Is the power zone calculator free? Yes, completely and forever. No email, no account, no paywall on the result.
Do I need a power meter? To train by power zones, yes. To find your zones you only need your FTP, which you can estimate from a 20-minute, 8-minute or ramp test inside the tool. Without a meter, use heart-rate or pace zones.
Is "powerzone calculator" the same thing? Yes. "Power zone calculator," "powerzone calculator" and "FTP zone calculator" all mean the same tool: turning your FTP into cycling power zones.
Start with the FTP & power zone calculator, or browse every calculator to set zones for your sport.
Sources
- Allen, H. & Coggan, A. Training and Racing with a Power Meter (2nd ed., VeloPress, 2010)
- Coggan, A. Power Training Levels, TrainingPeaks
- FTP-estimation factors (20-minute ×0.95, 8-minute ×0.90, ramp ×0.75) follow the standard field-test protocols described in the same sources