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HEALTH & FITNESS

Body Fat Calculator

Estimate body-fat percentage with the U.S. Navy method.

100% free No sign-up Private — runs in your browser Instant results
KEY TAKEAWAYS
  • Estimate body-fat percentage with the U.S. Navy method.
  • Free to use — no sign-up, no account and no usage limits.
  • Runs entirely in your browser, so the numbers you enter stay private.
  • Works on desktop and mobile with instant, accurate results.

Last updated: June 2026

About the Body Fat Calculator

Enter a few tape measurements (neck, waist, and hip for women) plus your height to estimate body-fat percentage, fat mass and lean mass.

Frequently asked questions

How accurate is the Navy method?

It's typically within a few percent of a DEXA scan for most people — good enough to track changes over time.

Free online tool from ConvertFleet. Calculations run entirely in your browser — nothing you type is sent anywhere. Results are estimates for general guidance only.