Cycling Power Zones Calculator

Power zones based on FTP guide structured cycling training.

How the Math Works

The Cycling Power Zones Calculator uses your Functional Threshold Power (FTP) as the foundation for determining five distinct training zones. FTP represents the maximum power you can sustain for approximately one hour, measured in watts. The calculator applies percentage-based thresholds derived from the Coggan power zone methodology: Zone 1 is 0-55% of FTP, Zone 2 is 56-75%, Zone 3 is 76-90%, Zone 4 is 91-105%, and Zone 5 is 106-120% of your FTP. Each zone corresponds to different physiological effects and training adaptations, allowing precise targeting of specific energy systems during workouts.

Practical Applications

To use this calculator, first determine your FTP through a standardized test or use a recent power measurement from a long ride. Enter this value into the calculator to instantly generate your personalized power zones. During training, use these zones to structure your workouts by targeting specific power ranges. For example, an endurance ride might stay within Zone 1-2, while a threshold session focuses on Zone 4 efforts. Most cycling computers and training apps can display these zones in real-time, allowing you to adjust your effort based on current power output relative to your FTP.

Day-to-Day Use

Power zones transform your cycling training from guesswork to precision science. Instead of wondering if you're working hard enough, you can see exactly which energy system you're training at any moment. This leads to more efficient workouts that produce specific adaptations—building aerobic base fitness in Zone 2, improving lactate threshold in Zone 4, or developing sprint power in Zone 5. Over time, tracking your performances within specific zones helps you understand how your fitness evolves and when to increase your FTP through targeted training.

Worked example

FTP 250 W → endurance to 188 W, threshold to 263 W.

FAQ