Capstan Winch Calculator

Capstan equation — holding force, friction, and mechanical advantage for wraps around a post.

Calculator Numbers & Math Updated Apr 20, 2026
How to Use
  1. Enter load, wraps, and friction coefficient.
  2. Hold force needed drops exponentially with wraps.
Input
Presets
Result

Show Work

Enter values to see the step-by-step calculation.

Formula

Capstan equation
T_hold = T_load / e^(μ·θ) — θ = wraps × 2π
Typical μ
rope on wood ≈ 0.3 · rope on steel ≈ 0.25 · nylon ≈ 0.35

About the Capstan Winch Calculator

Use the Capstan Winch Calculator — a free, easy tool for everyday maths and number work. Nothing is uploaded, and you do not need an account. Capstan equation — holding force, friction, and mechanical advantage for wraps around a post.

How it works

Put each value in its box and read the answer as you go. Because it recalculates live, you can play with the inputs to see how each one moves the result — handy for checking your own working or planning ahead. Everything happens on your device, so it is fast and private.

Want the deeper story? The Knowledge Base explains the ideas behind the tools in more detail.

Frequently Asked Questions

How do I use the Capstan Winch Calculator?

Just type your numbers. The answer shows up right away — there is no button to press. Change anything and it updates by itself.

Do I need to install or sign up for anything?

Not at all — it runs in the browser with nothing to install and no account. After it loads once, it even works without an internet connection.

Is my information private?

Yes. Everything happens in your browser. Nothing you type is sent to a server or saved anywhere.

Common Use Cases

Nothing to set up

Open the page and start. There is nothing to install, and no account to make.

Check your work

Worked it out yourself? Use the Capstan Winch Calculator to make sure your answer is right.

Learn while you do it

Seeing what you put in and what comes out helps you understand how they fit together.

No data leaves your browser

The tool runs locally, so whatever you enter stays with you and only you.

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