Life Events

Body Fat Calculator

Enter your gender, height, neck, and waist measurements (plus hip for women) to estimate body fat percentage using the widely-used US Navy circumference method. A quick, tape-measure-only alternative to more involved body composition testing.

  • Nothing leaves your device
  • Runs entirely in your browser
  • Free, no account needed
Use Body Fat Calculator - free

Frequently asked questions

How accurate is the US Navy method?

It is a reasonably accurate estimate for most body types using simple tape measurements, though it can be less precise for very lean or very muscular individuals compared to methods like DEXA scans.

Where exactly should I measure?

Neck: just below the larynx. Waist: at the navel. Hip (women only): at the widest point of the hips.

Is my measurement data stored?

No, the calculation happens entirely in your browser and nothing is saved or transmitted.

Estimate body fat percentage - free, private.

Open Body Fat Calculator
  • Nothing leaves your device
  • No upload required
  • No account needed
  • Unlimited use, always free