Cycling Power from Speed Calculator

About this calculator

Power at the pedals equals the sum of aerodynamic drag, rolling resistance, gravitational resistance and drivetrain losses, all multiplied by speed — a physics-based model similar to the cycling power equation published by Martin and colleagues in 1998, used to estimate the power output a given speed actually requires.

Cyclists without a power meter use it to estimate their effort, race engineers use it to model time-trial pacing strategy, and triathletes use it to plan realistic bike-leg splits before race day.

This calculator takes your speed, weight, CdA, rolling resistance and grade, and returns the estimated power output in watts.