Turn your FTP, or a 20-minute, 8-minute or ramp test result, into seven Coggan power zones in watts, plus your watts per kilogram and fitness band.
W
kg
Results
Calculated
Functional threshold power
—
W, estimated or entered
Power-to-weight
—
W/kg at FTP
Zone 1: Active recovery
—
up to 55% of FTP
Zone 2: Endurance
—
56–75% of FTP
Zone 3: Tempo
—
76–90% of FTP
Zone 4: Threshold
—
91–105% of FTP
Zone 5: VO2 max
—
106–120% of FTP
Zone 6: Anaerobic
—
121–150% of FTP
Zone 7: Neuromuscular
—
above 150% of FTP
Ready
Choose how your power was measured, enter it in watts (weight optional), then press Calculate.
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What this calculator finds
Power zones split your effort into ranges relative to your functional threshold power (FTP), the highest average power you can sustain for roughly an hour. Training in the right zone matters: easy endurance work builds aerobic capacity, while threshold and VO2 max intervals raise the ceiling. This calculator turns a known FTP, or the result of a common field test, into seven training zones in watts and, if you give your weight, your power-to-weight ratio.
It is meant for road, gravel and indoor riders who train with a power meter or smart trainer.
The method
FTP is entered directly, or estimated as 0.95 × a 20-minute test, 0.90 × an 8-minute test, or 0.75 × the best minute of a ramp test.
Zones follow the Coggan model: Z1 up to 55% of FTP, Z2 56–75%, Z3 76–90%, Z4 91–105%, Z5 106–120%, Z6 121–150%, Z7 above 150%.
W/kg is FTP divided by body weight in kilograms.
Worked example
A rider has an FTP of 260 W and weighs 72 kg, the default inputs. Their power-to-weight ratio is 260 / 72 = 3.61 W/kg.
The zones are: Z1 0–143 W (0.55 × 260), Z2 146–195 W, Z3 198–234 W, Z4 237–273 W, Z5 276–312 W, Z6 315–390 W and Z7 above 390 W. If the same rider had instead entered a 20-minute test average of 274 W, the calculator would multiply by 0.95 to get an FTP of about 260 W and produce the same zones.
Common mistakes and how to read the result
Testing tired. A poor test underestimates FTP and sets every zone too low.
Using the wrong test factor. Selecting the 20-minute option with an 8-minute number overstates FTP.
Treating zones as hard lines. Power varies with terrain and fatigue; use zones as guides.
Comparing W/kg between riders without context. The fitness band is a rough guide only.
Frequently Asked Questions
Why is my 20-minute power multiplied by 0.95?
Most people cannot hold their 60-minute maximum for more than about 20 minutes at a fully rested test. The 0.95 factor is the standard estimate of the hour-long power from a 20-minute effort, and works best after a proper warm-up.
Are these the Coggan zones?
Yes. They use the seven-zone model popularized by Dr. Andrew Coggan: Zone 1 below 55% of FTP, Zone 2 56 to 75%, Zone 3 76 to 90%, Zone 4 91 to 105%, Zone 5 106 to 120%, Zone 6 121 to 150%, and Zone 7 above 150%.
How often should I retest my FTP?
Every 4 to 8 weeks during a training block, or whenever your rides feel much easier or harder than the zones suggest. Zones based on an old FTP quickly drift out of date.
Do heart-rate zones match power zones?
Not exactly. Heart rate lags power and drifts with heat, fatigue and caffeine. Power zones respond instantly, so they are the better control for intervals; heart rate is a useful cross-check on long steady rides.
Practical Guide for Cycling Power Zones Calculator - FTP Based Training
Cycling Power Zones Calculator - FTP Based Training is most useful when the inputs reflect the situation you are actually planning around, not a best-case estimate. Treat the result as a decision aid: it gives you a structured way to compare assumptions, spot outliers, and decide what to verify next. For Sports work, the most important review lens is repeatability, fatigue, recovery, pacing, training load, and conditions on the day.
Start with a baseline run using values you can defend. Then change one assumption at a time and watch which output moves the most. If one input dominates the result, spend your verification time there first. If several inputs have similar influence, use a conservative scenario and an optimistic scenario to create a practical range instead of relying on a single exact number.
Before acting on the result, compare the result with recent sessions, race logs, and coach feedback instead of relying on a single best effort. This is especially important when the calculator supports a purchase, project plan, performance target, or operational decision. The calculator can make the math consistent, but the quality of the conclusion still depends on current data, clear units, and assumptions that match your real constraints.
When the output looks surprising, slow down and inspect each input in order. A small change in one high-leverage field can move the final number more than several low-leverage fields combined. For Cycling Power Zones Calculator - FTP Based Training, that means you should first confirm the value with the greatest scale, then confirm the value with the greatest uncertainty, then rerun the calculator with conservative and optimistic assumptions. This sequence turns the calculator from a single answer into a practical decision range.
Review Checklist
Confirm every input uses the unit and time period requested by the calculator.
Run a low, expected, and high scenario so the answer has a useful range.
Check whether rounding or a missing decimal place changes the decision.
Update the calculation each training block, after a tune-up event, or when volume and intensity change.