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Free training tool

FTP & Power Zones
Calculator.

Estimate your FTP from a 20 minute test, then get all seven Coggan training zones in watts and your power to weight ratio in W/kg.

Your numbers

Ride the 20 minute effort all-out and evenly paced for the most accurate estimate.

Your FTP
238
watts
3.18
W/kg · moderate
Coggan power zones
Z1 Active recovery —
Z2 Endurance —
Z3 Tempo —
Z4 Threshold —
Z5 VO2 max —
Z6 Anaerobic —
Z7 Neuromuscular —

Zones are watt ranges from your FTP using the Coggan percentages. W/kg uses your body weight in kilograms.

The maths

How the calculator works

Everything hangs off one number, your FTP: the highest power you can hold for about an hour. The zones and W/kg are simple percentages and divisions of it.

×
FTP estimate = 20 minute average power × 0.95. The 5 percent trims the 20 minute number down to a one-hour sustainable power.
%
Power zones = FTP × the Coggan band percentages. Zone 4 (91 to 105 percent) sits right around your FTP.
÷
Power to weight = FTP ÷ body weight in kilograms. The W/kg figure that predicts climbing better than raw watts.
=
Direct FTP Switch modes to type your FTP straight in and skip the 20 minute maths entirely.

Train most of your endurance base in Zone 2, build sustained power around Zone 4 threshold, and use short, hard Zone 5 and 6 efforts sparingly. Retest every four to six weeks with the same protocol so your zones stay accurate as you get fitter.

Want a printable power zone chart?
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FAQ

FTP and power zones FAQ

Ride an all-out, evenly paced 20 minute effort and take your average power for it. Multiply that number by 0.95 to estimate your Functional Threshold Power. The 5 percent reduction accounts for the fact that a 20 minute effort is slightly higher than the power you could hold for a full hour.

The Coggan model splits training into seven zones as a percentage of FTP: Zone 1 active recovery (under 55 percent), Zone 2 endurance (56 to 75), Zone 3 tempo (76 to 90), Zone 4 threshold (91 to 105), Zone 5 VO2 max (106 to 120), Zone 6 anaerobic (121 to 150) and Zone 7 neuromuscular (over 150 percent).

Raw watts mean little without body weight, which is why power to weight (W/kg) matters more. A fit recreational rider is often around 2.5 to 3.5 W/kg at threshold, strong amateurs sit at 3.5 to 4.5, and elite riders exceed 5. A 250 watt FTP is strong for a 75 kg rider but modest for a 90 kg rider.

Power to weight ratio is your FTP in watts divided by your body weight in kilograms, giving W/kg. It predicts climbing and sustained-effort performance far better than raw watts, because on a climb you have to lift your own weight. This calculator works it out once you enter your weight.

Every four to six weeks during focused training is typical, since that is roughly how long a training block takes to produce a measurable change. Retesting too often just adds fatigue and noise. Keep the test protocol identical each time so the numbers are comparable.

Yes. Switch the input mode to I know my FTP and type it in, and the calculator will build your seven zones and W/kg straight from that number. Use the 20 minute test mode only when you want the tool to estimate FTP for you from a test effort.