Steady Bicycle Power Calculator
Break down gravity, rolling and longitudinal aerodynamic forces at an entered ground speed and signed wind.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Resolve gravity and normal force on the road slope. Use signed relative air speed for drag, add forces, multiply by ground speed and apply drivetrain efficiency for positive demand.
Wheel P=v[mg sinθ+Crr mg cosθ+½ρCdA(v+wind)|v+wind|]; θ=atan(grade)
Worked example
At 36 km/h, no slope, no rolling resistance, no wind, air density 1.2 kg/m³ and CdA=0.4 m², wheel power is 240 W. At 80% drivetrain efficiency pedal power is 300 W.
Assumptions and input details
Steady motion in a straight line; no acceleration, crosswind, changing terrain or tire/bearing temperature model. Coefficients are entered assumptions, not personal performance recommendations. Negative wheel demand is a braking/dissipation requirement. Mechanical work is not dietary energy expenditure.
References: Cycling resistance model research
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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