FTP Calculator
Estimate your Functional Threshold Power (FTP) from a 20-minute, ramp or 8-minute test, then see your watts per kilogram, the seven Coggan power training zones and matching heart-rate zones.
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How to use the FTP Calculator
- Pick your test type: 20-minute, ramp, 8-minute or a known FTP.
- Enter the test power in watts (average power, or best 1-minute power for a ramp test).
- Add your body weight to see W/kg.
- Enter a heart rate (20-minute average or known LTHR) for heart-rate zones.
- Use the zone tables to set targets for your rides and intervals.
FTP test conversion factors
| Test | What you record | FTP formula | Example |
|---|---|---|---|
| 20-minute test | Average power for 20 min all-out | × 0.95 | 260 W → 247 W |
| Ramp test | Best 1-minute power | × 0.75 | 320 W → 240 W |
| 8-minute test | Average of the better of two 8-min efforts | × 0.90 | 280 W → 252 W |
| 60-minute effort | Average power for 1 hour | × 1.00 | 240 W → 240 W |
These factors are averages. Riders with strong anaerobic power often overestimate FTP on ramp tests, while very aerobic riders may underestimate it.
What each power zone trains
| Zone | % FTP | Typical use |
|---|---|---|
| Z1 Active recovery | ≤ 55% | Easy spins and recovery days |
| Z2 Endurance | 56–75% | Long rides, aerobic base |
| Z3 Tempo | 76–90% | Steady group rides, extended efforts |
| Z4 Lactate threshold | 91–105% | 2 × 20 min, 3 × 12 min intervals |
| Z5 VO₂max | 106–120% | 3–8 min intervals |
| Z6 Anaerobic capacity | 121–150% | 30 s – 3 min hard efforts |
| Z7 Neuromuscular | > 150% | Sprints under 15 s |
Tips for a good test
- Warm up for 15–20 minutes with a few short, hard efforts before the test.
- Pace a 20-minute test evenly; starting too hard is the most common mistake.
- Use the same power meter or trainer each time; different devices can read a few percent apart.
Frequently asked questions
What is FTP?
Functional Threshold Power is the highest average power a cyclist can sustain for about an hour, in watts. It is used to set training zones and track fitness. Most riders estimate it from a shorter test rather than riding all-out for 60 minutes.
How do I calculate FTP from a 20-minute test?
Multiply your average power for the 20-minute all-out effort by 0.95. For example, 250 W for 20 minutes gives an FTP of about 238 W. The 5% reduction accounts for the shorter duration.
How is FTP calculated from a ramp test?
In a ramp test the power rises every minute until you cannot continue. FTP is commonly estimated as 75% of your best 1-minute power. A rider whose best minute was 320 W would have an FTP of about 240 W.
What are the Coggan power zones?
Andrew Coggan's seven zones are: Z1 active recovery (up to 55% of FTP), Z2 endurance (56–75%), Z3 tempo (76–90%), Z4 lactate threshold (91–105%), Z5 VO2max (106–120%), Z6 anaerobic capacity (121–150%) and Z7 neuromuscular power (above 150%).
What is a good FTP?
It depends on weight, so W/kg is the better comparison. Many untrained adults are around 2 W/kg, regular club riders 3 to 4 W/kg, strong amateur racers 4 to 5 W/kg and professional riders above 5.5 W/kg.
How do I find my threshold heart rate?
A common estimate is 95% of your average heart rate during a 20-minute all-out test. You can also use the average heart rate of the last 20 minutes of a 30-minute solo time trial. Heart-rate zones are then set as percentages of that value.
How often should I retest FTP?
Every 4 to 8 weeks during structured training, or after a training block. Test under similar conditions each time: same bike or trainer, warm-up, time of day and fueling.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.