FTP Calculator

The FTP Calculator helps you estimate cycling FTP from a hard test effort. Start with the numbers you actually have, choose the unit that matches your watch or race plan, and use the result as a plain-English checkpoint. It is built for runners in the US who think in miles first but still need clean kilometer support for workouts, races, and coaching notes. Next steps: related calculator 1, related calculator 2, related calculator 3.

Your test
The seven Coggan power-training zones from your FTP
Zone% of FTPPower
Z1 · Active recovery<56%≤132 W
Z2 · Endurance56–75%133–178 W
Z3 · Tempo76–90%181–214 W
Z4 · Threshold91–105%216–249 W
Z5 · VO₂max106–120%252–285 W
Z6 · Anaerobic121–150%287–356 W
Z7 · Neuromuscular>150%≥359 W
Functional Threshold Power238 W
Power-to-weight at threshold3.17 W/kg
Coggan power profileGood — 3.17 W/kg at threshold

250 W · 75 kg

How it works

FTP = 0.95 × best 20-minute average power

This page keeps the calculation centered on one relationship: FTP = 0.95 × best 20-minute average power. Inputs are normalized before the final display, which keeps mile, kilometer, pace, speed, or zone outputs from drifting because of rounding. Use the number as a consistent model output, then layer in terrain, weather, recovery, and race execution. Keep the fixed reference values in view: 20, 20 m, 0.95, 5%, 55%, 150%.

Sources

FAQ

When should I use the ftp calculator?

Use it when you want a fast planning number before a run, race, workout, or gear decision. It gives you a consistent estimate without asking you to create an account. Keep the fixed reference values in view: 20 m, 0.95.

What inputs matter most?

The best result comes from honest, current inputs. Recent race times, realistic body measurements, accurate workout data, and the correct unit setting matter more than perfect formatting. Keep the fixed reference values in view: 20, 5%, 0.95.

How should I read the result?

Treat the output as a planning reference, not a promise. Use it to compare options, set a target range, or sanity-check your watch data before making the final call. Keep the fixed reference values in view: 2.5–3.0 W, 3.5–4.0, 5.0 W.

Does this work in miles and kilometers?

Yes. PacerRunning is written for US runners first, so miles are easy to use, but metric conversions are kept alongside them where the tool needs both views. Keep the fixed reference values in view: 2, 3, 4, 5, 6–7.

Why might my real-world result differ?

Terrain, wind, heat, sleep, fueling, training fatigue, and measurement error can all move the real outcome away from the estimate. The FTP ftp calculator cannot see those details. Keep the fixed reference values in view: 4–8.

Can beginners use it?

Yes. You do not need advanced training knowledge. Enter the numbers you know, read the result as a guide, and keep your effort comfortable when you are unsure. Keep the fixed reference values in view: 8, 0.90, 60, 20, 0.95 m.

FTP Calculator results are estimates from the entered data and the cited method. They are useful for planning and comparison, but they are not a diagnosis, prescription, guaranteed race result, or substitute for a coach or clinician. Keep the fixed reference values in view: 20.

Embed this calculator

Add the ftp calculator to your website or club page — free, no sign-up. Paste this snippet where you want the calculator to appear:

<script src="https://pacerrunning.net/embed/ftp-calculator.js" async></script>