Body Fat Calculator
Estimate body fat percentage using the US Navy circumference method. Measure your neck, waist, and height (and hips for women) to see your result.
e.g. 178
Narrowest point
At navel
Estimated Body Fat
22.2%
Average
Body Fat Categories (male)
The US Navy method has ~±3.5% accuracy. Results are estimates — consult a healthcare professional for clinical measurement.
- 100% free — no account needed
- Runs in your browser
- Nothing is uploaded
Frequently asked questions
Is Body Fat Calculator really free?
Yes. Body Fat Calculator is completely free on PureBrowser — every feature, with no account, no trial, and no credit card.
Does Body Fat Calculator upload my data?
No. Body Fat Calculator runs entirely inside your browser, so anything you type, paste, or open stays on your own device.
Do I need to sign up or install anything?
Neither. There is no account and nothing to download — open the page and Body Fat Calculator is ready to use on desktop or mobile.
Does Body Fat Calculator work offline?
Once the page has loaded, yes. All of the processing happens locally in your browser, so it keeps working without a connection.
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