Cycling FTP Calculator

Calculate your Functional Threshold Power (FTP) from a 20-minute test, ramp test, or 8-minute test. Set Coggan power zones for structured cycling training.

About the Cycling FTP Calculator

Functional Threshold Power (FTP) is a widely used benchmark in power-based cycling, usually defined as the highest average power you can sustain for about an hour.

This calculator estimates FTP from three common test protocols: the 20-minute test, the ramp test, and the 8-minute test. It also generates Coggan-style power zones for training.

Use FTP as a practical anchor for workouts and repeat testing, not as a complete description of cycling performance.

Why Use This Cycling FTP Calculator?

It is useful when you want one repeatable number to set power zones and compare test results over time. FTP helps organize training, but it is still an estimate and only one part of the broader performance picture.

How to Use This Calculator

  1. Select your test type (20-minute, ramp, or 8-minute).
  2. Enter your average power for the test duration.
  3. View your estimated FTP.
  4. Review your seven Coggan power training zones.
  5. Optionally enter your body weight for W/kg comparison.
  6. Use the zones to structure interval and endurance workouts.

Formula

FTP estimation by test type: • 20-minute test: FTP = 95% of 20-min avg power • Ramp test: FTP = 75% of best 1-minute avg power • 8-minute test: FTP = 90% of avg of two 8-min intervals Coggan Power Zones: • Z1 Active Recovery: <55% FTP • Z2 Endurance: 56–75% FTP • Z3 Tempo: 76–90% FTP • Z4 Lactate Threshold: 91–105% FTP • Z5 VO2max: 106–120% FTP • Z6 Anaerobic: 121–150% FTP • Z7 Neuromuscular: >150% FTP

Example Calculation

Result: FTP = 238 watts

For a 20-minute test with 250W average: FTP = 250 × 0.95 = 237.5, rounded to 238W. This means your Zone 2 (endurance) range is 133-178W, and your Zone 4 (threshold) range is 216-250W. Training at these precise intensities targets specific physiological adaptations.

Tips & Best Practices

The Science Behind FTP

FTP approximates the boundary between sustainable and unsustainable exercise intensity. Below FTP, lactate production and clearance are balanced; above FTP, lactate accumulates progressively. Training at and around FTP improves this balance, raising the power you can sustain.

Coggan Power Zones Explained

Dr. Andrew Coggan's seven-zone model is the standard for power-based training. Each zone targets a specific physiological adaptation: Z1-Z2 build aerobic base, Z3-Z4 develop threshold and tempo fitness, Z5 improves VO2max, and Z6-Z7 develop anaerobic capacity and neuromuscular power. A balanced training plan includes work across all zones with periodized emphasis.

FTP vs. Other Metrics

While FTP is the most practical training metric, it's not the only one. Critical Power (CP), w' (anaerobic work capacity), and VO2max provide additional insights. FTP is most useful for events lasting 20 minutes to several hours; shorter events rely more on anaerobic capacity.

Sources & Methodology

Last updated:

Methodology

This worksheet converts common field-test results into an FTP estimate using the standard shortcuts built into the page: 95% of a 20-minute test, 75% of a ramp-test best minute, or 90% of the average of an 8-minute protocol. It then multiplies FTP by the Coggan zone percentages to create training ranges. The result is a practical training anchor, not a direct laboratory threshold measurement.

Sources

Frequently Asked Questions

What is a good FTP?

FTP varies widely. For recreational cyclists, 150-200W is typical. Competitive amateur cyclists often achieve 250-300W. Elite cyclists may exceed 350W. However, FTP relative to body weight (W/kg) is more meaningful for performance comparison.

Why is FTP 95% of 20-minute power, not 100%?

Because FTP represents one-hour power, and most people can sustain about 5% more power for 20 minutes than for 60 minutes. The 95% factor approximates this relationship. Some athletes may need 92-97% depending on their anaerobic contribution.

How often should I retest FTP?

Every 6-8 weeks during structured training, or whenever you feel your zones are too easy/hard. FTP can change significantly over a training block, especially for newer cyclists. Experienced cyclists may see smaller changes.

Which FTP test is best?

The 20-minute test is the most widely used field option for accuracy. The ramp test is popular for its simplicity and repeatability but may overestimate FTP for some riders. The 8-minute test is a shorter alternative with moderate accuracy.

Can I estimate FTP without a power meter?

Not accurately. Heart rate zones are an alternative for unstructured training, but power meters provide precise, instantaneous feedback that heart rate cannot. Smart trainers with built-in power meters are the most accessible option.

Is indoor FTP different from outdoor FTP?

Yes, typically indoor FTP is 5-10% lower due to reduced cooling, mental monotony, and lack of road feel. If you train primarily indoors, test indoors. Use separate FTP values for indoor and outdoor training if possible.

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