Power-zone tool

Power Zones Calculator

Choose a zone model, enter FTP or CP, and generate non-overlapping power zones in watts.

POWER ZONESFTP / CP

Calculator

Enter your FTP/CP and generate zone boundaries in watts.

Inputs

Generate zone boundaries from a reference power and zone model.

Zone model

7 zones

Reference

Value (W)

Whole watts recommended.

Boundary values are assigned to the higher zone so ranges do not overlap.

Zones

Enter a reference power to see zones.

Zone	%	Watts
Enter FTP/CP to generate zones.

Training Zones Explained

7 zones — what each zone is for.

Z1 Active Recovery

Active recovery. Very easy work for warm-up, cool-down, and recovery.

Z2 Endurance

Endurance. Aerobic base work for long sessions and steady volume.

Z3 Tempo

Tempo. Controlled steady-hard work to improve aerobic durability.

Z4 Threshold

Threshold. Sustained hard efforts that raise your sustainable power.

Z5 VO2 Max

VO2 / high intensity. Shorter intervals to improve high-aerobic capacity.

Z6 Anaerobic

Anaerobic capacity. Very hard efforts with heavy anaerobic contribution.

Z7 Neuromuscular

Neuromuscular / sprint. Maximal, short bursts focusing on speed and coordination.

How to use power zones

Enter a current FTP or CP

Use the reference you train with now. Re-test or update it when your fitness changes.

Choose a zone model

Pick Friel, Vance, or Stryd based on your sport, device, and coaching setup.

Use the ranges in workouts

Copy the zone table and use it for interval targets, endurance rides/runs, and post-workout review.

What are power zones?

For athletes setting cycling or running power targets.

Power zones divide your FTP or CP into repeatable intensity ranges. They help you turn one reference power into easy, endurance, tempo, threshold, VO2, and anaerobic targets so workouts can be prescribed and reviewed consistently.

FAQ

How accurate are these zones?

Zone boundaries are only as good as your FTP/CP. Re-test or re-estimate regularly, and adjust based on fatigue, terrain, and sport.

Should I use FTP or CP?

Use the reference that matches your training setup. Cyclists often use FTP. Runners with power often use CP. If you have both, pick the one you update most consistently.

Why do zone boundaries look off by 1W?

This tool treats model percentages as non-overlapping ranges. A boundary value is assigned to the higher zone to avoid overlap, which can create a 1W difference after rounding.

Models

Choose the model that best matches your sport, device, and training habits.

Friel (7 zones)

A classic 7-zone model widely used for cycling training based on FTP.

Vance (7 zones)

A 7-zone model commonly referenced for running-with-power, mapping the full intensity spectrum.

Stryd (5 zones)

A simpler 5-zone structure popular for running with power, typically anchored to CP.

Keep calibrating your intensity targets

Estimate FTP training load from file Estimate max heart rate for load zones Calculate VDOT for running load targets

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