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FTP & Cycling Power Zone Calculator

One test number in. Seven zones and an honest W/kg out.

  • 2 min
  • Free
  • No sign-up

Functional threshold power is the highest power you could hold for about an hour, and it is the number every cycling session is prescribed against. Which test you did changes how it is calculated — a ramp test and a 20-minute test need different corrections — so this tool asks first and applies the right one, then shows where your watts per kilogram actually sits.

The correction factor differs per protocol. Choosing the wrong one shifts every zone.

For a ramp test, enter your best one-minute power. For "I know my FTP", enter the FTP itself.

Power-to-weight benchmarks differ substantially between male and female athletes.

Example result. A worked example for a rider who averaged 250 watts for a 20-minute test at 75 kg — a very typical age-group triathlete result, and a good illustration of why the 0.95 correction matters. Fill in the form above for your own.
238 W FTP

Recreational — 3.17 W/kg

Your FTP is 238 W — that is 3.17 W/kg, which sits in the recreational band

Calculated from your 20-minute time trial: 95% of your 20-minute average. Raw watts move you along the flat; watts per kilogram decide what happens the moment the road tilts up, which is why the chart below is in W/kg rather than watts.

Where your power-to-weight sits

NoviceNoviceRecreationalRecreationalCompetitiveCompetitiveStrongStrongEliteEliteYou — 3.17 W/kg
View as a table
BandScore
Novice1.6–2.5 W/kg
Recreational2.5–3.2 W/kg
Competitive3.2–4.0 W/kg
Strong4.0–4.8 W/kg
Elite4.8–6.0 W/kg
YouYou — 3.17 W/kg

Compared against male benchmarks. These describe sustainable threshold power per kilogram, not sprint power, and they shift by roughly 15% between male and female athletes.

Your seven power zones

Set these on your head unit. Zones four and above are where the hard sessions are prescribed; zones two and three are where the hours are.

ZonePower% of FTPWhat it is for
Z1 Active recoveryUp to 132 W0–55%Spinning to clear the legs. Not training.
Z2 Endurance133–180 W56–75%All-day pace. Where long rides live, and most of your hours.
Z3 Tempo181–216 W76–90%Steady and firm. Long-course race pace sits here.
Z4 Lactate threshold217–251 W91–105%At threshold. Raises the ceiling everything else sits under.
Z5 VO2max252–287 W106–120%3–8 minute intervals. Top-end aerobic power.
Z6 Anaerobic capacity288–358 W121–150%30 seconds to 3 minutes. Bridging and surges.
Z7 Neuromuscular359 W and above151–250%Sprints under 15 seconds. Force, not fitness.

What to do with this

For long-course racing you will spend the bike leg in zone three, at roughly 181 to 214 watts, not at threshold. The purpose of raising FTP is to make that zone-three number a smaller share of your ceiling, so you arrive at the run with your legs intact.

Retest every six to eight weeks with the same protocol. Comparing a ramp test against a 20-minute test tells you almost nothing, because the correction factors bake in different assumptions about your anaerobic contribution.

If you only change one thing after reading this, make it the long ride: most age-group triathletes ride their easy rides too hard and their hard rides too easy, and both are visible the moment the zones exist.

Tri Alliance sessions that close these gaps

  • Group ride Zones are worth having because the sessions get built on them. Squad rides are prescribed in power zones.
  • Brick session (bike into run) Long-course race power sits in zone three, and the only way to know whether you can run off it is to rehearse it.

A maximal cycling test is a genuinely hard effort. Get medical clearance first if you are new to intense exercise, returning from illness or injury, or have any history of heart or blood-pressure problems.

The short answer

Functional threshold power (FTP) is the highest average power a cyclist can sustain for approximately one hour, and it is the anchor for all cycling training zones. It is estimated from a field test with a protocol-specific correction: 95% of average power for a 20-minute time trial, 90% for an 8-minute test, and 75% of the best one-minute power for a ramp test. Coggan's seven power zones are then set as percentages of FTP: Zone 1 active recovery below 55%, Zone 2 endurance 56–75%, Zone 3 tempo 76–90%, Zone 4 lactate threshold 91–105%, Zone 5 VO2max 106–120%, Zone 6 anaerobic capacity 121–150%, and Zone 7 neuromuscular power above 150%. Watts per kilogram — FTP divided by body mass in kilograms — matters more than raw watts for any riding that involves climbing, and typical recreational cyclists sit between 2.5 and 3.2 W/kg.

How to use this tool

  1. Pick the test protocol you actually completed — the correction factor is different for each one.
  2. Enter the average power for that test. For a ramp test, that means your best single minute, not the whole ramp.
  3. Enter your body weight in kilograms, measured in the morning rather than after dinner.
  4. Read your FTP, your watts per kilogram, and all seven zones.
  5. Set the seven zones on your head unit, and retest every six to eight weeks during a build.

Common questions

How do I do a 20-minute FTP test?

Warm up for at least 15 minutes including two or three short hard efforts, then ride as hard as you can evenly sustain for 20 minutes. Your FTP is 95% of the average power for that 20 minutes. Pace it flat — going out too hard costs more in the back half than you gain in the front, and a fading test underestimates your FTP. Do it on a stretch of road without junctions, or on a trainer, and do it alone.

Why is FTP 95% of my 20-minute power?

Because FTP is defined as roughly a one-hour power, and almost nobody can hold their 20-minute power for a full hour. The 5% deduction is an empirical adjustment that lands most trained cyclists close to their true hour power. It is an approximation rather than a physiological law — riders with a big anaerobic contribution tend to have their FTP overestimated by the 20-minute test, and diesel-engine riders underestimated. If your threshold sessions feel impossible at the prescribed watts, your correction was too generous.

Is a ramp test as accurate as a 20-minute test?

It is more repeatable and far less unpleasant, but it is more sensitive to your anaerobic capacity. A ramp test takes 75% of your best one-minute power, so a rider with a strong sprint tends to come out with an inflated FTP and then finds their threshold intervals undoable. A 20-minute test hurts more but sits closer to what threshold work will actually feel like. Use the same protocol every time you retest, because the comparison between tests matters more than the absolute number.

What is a good FTP for a triathlete?

Raw watts are close to meaningless without body mass, so use watts per kilogram. Recreational cyclists typically sit between 2.5 and 3.2 W/kg, competitive age-group triathletes between 3.2 and 4.0, strong age-groupers between 4.0 and 4.8, and elite athletes above that. For long-course racing, sustainable W/kg and good aerodynamics matter far more than peak FTP, because you will be riding at 70 to 80% of threshold rather than at it.

How often should I retest my FTP?

Every six to eight weeks during a build phase, and after any block where the sessions have started to feel easy at the prescribed power. Stale FTP is the quiet killer of a training plan: as you get fitter, an unchanged FTP turns your threshold sessions into tempo sessions, and your zone-two rides drift down into recovery. If you are consistently completing every interval comfortably, the number is out of date rather than the session being easy.

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