How accurate is this estimate?

The Deurenberg formula is typically accurate to within about 4 percentage points for most adults, but it is less reliable for athletes and children.

What is a healthy body fat percentage?

Roughly 10 to 25% for men and 18 to 32% for women, though the ideal varies with age and activity level.

Body Fat Calculator | Tsinglin.tech

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Sex

BMI

Age

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Estimate your body fat percentage from your BMI, age and sex using the Deurenberg formula. Free, nothing is stored.

How to use Body Fat Calculator

Open the toolNo signup and nothing to install; it works as soon as the page loads.
Set “Sex”
Set “BMI”
Set “Age”
Read the resultChange any input and the result is recalculated immediately.

Worked example with the defaults

ESTIMATED BODY FAT · Within the healthy range for your sex: 20.6%

Nothing you enter leaves your device

All of the work happens inside your browser. Whatever you type is never packaged up and sent to a server, and no request this page makes carries it.

That makes it safe for contract amounts, personal details and internal documents you would rather not hand to a third party — close the tab and it is gone.

What this tool does not do

Body Fat Calculator only does what a browser can do on its own — it talks to no backend service. So it keeps no history for you and syncs nothing across devices; if you need a record, copy or download the result.

It is also not a substitute for professional judgement. For legal, medical or tax decisions, treat the output as a starting point rather than a final answer.

Frequently Asked Questions

How accurate is this estimate?: The Deurenberg formula is typically accurate to within about 4 percentage points for most adults, but it is less reliable for athletes and children.
What is a healthy body fat percentage?: Roughly 10 to 25% for men and 18 to 32% for women, though the ideal varies with age and activity level.