Fitness

Body fat calculator

Estimate body fat percentage using the US Navy measurement method. Supports metric and imperial inputs.

Height (cm)

Weight (kg) optional

Neck (cm)

Waist (cm)

Hip (cm) — widest point

US Navy method (Hodgdon & Beckett). Waist measured at navel; neck just below larynx.

100% private. All processing happens locally in your browser — no files or data are ever sent to a server.

How to use Body fat calculator

01 Fill in the required values using the fields provided
02 Results calculate automatically as you type
03 Copy or note the result — all calculations stay on your device

Frequently asked questions

Common questions about Body fat calculator.

Is Body fat calculator free to use?

Yes, Body fat calculator is completely free. No account, subscription, or payment is ever required — just open the page and start using it.

Does Body fat calculator upload my data to a server?

No. Body fat calculator runs entirely in your web browser using client-side JavaScript. Your files, text, and data never leave your device, making it 100% private.

Can I use Body fat calculator on my phone or tablet?

Yes. Body fat calculator is fully responsive and works on all modern smartphones, tablets, and desktop browsers without installing any app.

Are these results accurate enough to rely on?

Body fat calculator uses well-established formulas and provides accurate estimates for everyday use. For financial, medical, or legal decisions, always consult a qualified professional.

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About Body fat calculator

The US Navy Body Fat Method estimates body fat percentage from circumference measurements rather than specialist equipment. For men, it uses neck circumference, waist circumference at the navel, and height. For women, it additionally uses hip circumference. The formula uses a logarithmic regression that correlates well with more precise methods like DEXA scanning for most body types. The Navy method is the standard used in US military fitness assessments and provides a practical at-home estimate of body composition. Results are categorised into standard ranges: essential fat, athletic, fitness, average, and obese.