Cycling Power Calculator
Estimate power output from speed, weight and grade.
Enter your values
ⓘ Live results
Results
- Required power
- 146 W
- W/kg
- 1.83
- Speed
- 30 km/h
Quick answer
Cycling power output rises with speed, incline and rider+bike weight due to gravity, rolling resistance and aerodynamic drag.
P = (Crr x m x g + 0.5 x CdA x rho x v^2 + m x g x grade) x v
How to use the Cycling Power Calculator
- 1Enter target speed, total weight (bike + rider) and road grade.
- 2CdA of 0.30-0.35 is typical for an upright road position; lower values mean more aerodynamic.
- 3This models steady-state riding; wind and drafting will shift real-world power needs.
Worked example
Using the values the calculator loads with:
Inputs
- Speed30 km/h
- Total rider+bike weight80 kg
- Grade0 %
- CdA (aero drag area)0.32 m²
Results
- Required power146 W
- W/kg1.83
- Speed30 km/h
Frequently asked questions
What's a good W/kg?
Recreational riders sustain 2-3 W/kg; elite racers can exceed 5-6 W/kg for an hour.
Why does small speed change need big power?
Aerodynamic drag rises with the cube of speed, so going faster gets disproportionately harder.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.