Cycling Power Estimator
Estimate the power output (watts) needed to maintain a given speed, accounting for rolling resistance, aerodynamic drag, and gradient.
100% client-side · no upload
Estimated Power
Watts per kg
How to use
- Enter combined rider and bike weight in kilograms.
- Enter the target speed in km/h and road gradient in percent (negative for downhill).
- Click Estimate Power to see watts and watts per kilogram.
Related sport tools
- Running Pace Calculator — pace and speed conversion
- Training Load Calculator — RPE × duration session stress
- VO₂ Max Estimator — aerobic capacity from heart rate
- Heart Rate Zones — training zones from max HR
Preguntas frecuentes
- Is this cycling power calculator free?
- Yes, completely free with no signup and no usage limits.
- Does my data leave my device?
- No. All calculations run in JavaScript inside your browser. Nothing is sent to any server.
- Does it work on mobile?
- Yes. The calculator is mobile-first and works on iPhone Safari and Android Chrome.