Power-to-Weight Calculator

Calculates cycling power-to-weight ratio in watts per kilogram from power and body weight.

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Power(W)

Body weight(kg)

Result

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Estimate only — real results depend on terrain, weather, fatigue, conditions and individual fitness. Not medical or coaching advice.

Before you rely on this: First-pass guide only. Verify safety-critical or regulated work against the relevant standards, your project requirements and a qualified professional.

How to use this calculator

Enter your power (W) and body weight (kg).
Read your power-to-weight in W/kg.

How it works

Power-to-weight = watts ÷ body weight (kg). It strongly predicts climbing performance.

Worked example

250 W at 75 kg. = 3.33 W/kg.

Common mistakes

Using race-day weight you cannot maintain — base W/kg on a realistic, sustainable weight.
Comparing a 5-second sprint figure with a 20-minute one — always state the duration.

Tips

Times are estimates only — not medical or coaching advice. Always train safely and follow event rules.
Distances are editable: choose “Custom…” to enter your own course lengths.

Frequently asked questions

What is a good power-to-weight ratio?

Over a 20-minute effort, recreational cyclists sit around 2.5–3.5 W/kg, strong amateurs 4–5 W/kg, and pros above 6 W/kg.

Why does power-to-weight matter on climbs?

On a climb you mostly fight gravity, so watts per kilogram — not raw watts — sets how fast you go up.

FTP or peak power?

Use FTP for sustained climbing comparisons, or peak power for sprint comparisons — just be consistent.

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Cite this tool

Zerdly. (2026). Power-to-Weight Calculator. Retrieved from https://www.zerdly.com/tools/power-to-weight-calculator/

Tip: Enter any known values to calculate the remaining results.

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