Cycling Power Calculator
Estimate the power a given speed demands, split between air, rolling resistance and gradient.
Air resistance is a cube law
The aerodynamic term grows with the cube of speed, so going from 30 to 40 km/h needs well over twice the power on the flat. That is why aerodynamics dominates on flat roads and weight dominates on climbs, where the gradient term takes over and speed is too low for drag to matter much.
The formula
P = ½ρ·CdA·v³ + Crr·m·g·v + m·g·sin(θ)·v
Every result on this page comes from this formula. Nothing is rounded until the final display, so figures match a spreadsheet to the cent.
How to use the Cycling Power Calculator
- Fill in each field with your own figures — the defaults are only there as an example.
- The result updates as you type, so there is no button to press.
- Check the breakdown under the main result for the supporting numbers.
- Use the copy button to take the result with you, or share the link to reload the same inputs.
Cycling Power Calculator — frequently asked questions
Is this cycling power calculator free to use?
Yes. Every calculator on the site is free, needs no sign-up, and runs entirely in your browser, so your figures never leave your device.
How accurate is the result?
The maths is exact for the formula shown on the page. Accuracy in the real world depends on your inputs and on assumptions the formula cannot see, so treat the output as a well-grounded estimate rather than a quote.
Can I use it on my phone?
Yes. The page is responsive, weighs a few kilobytes and works offline once loaded, so it behaves the same on a phone as on a desktop.
What people search for
This page answers each of these searches. They are the exact phrases visitors use to find the cycling power calculator.
- cycling power calculator
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About this calculator
Written and reviewed by The Samsung Calculator editorial team. Every calculator is written against a published formula, reviewed against at least one independent reference implementation, and dated when it changes.
Last reviewed August 23, 2026 · Calculation runs client-side · No data collected · Report an error