Body Fat Calculator
Smart BMI & Targets by checkit.health
How the US Navy method works
The formula uses the difference between your waist and neck (and hip for women) plus your height to estimate fat. It’s surprisingly reliable for a tape-only method — typically within a few percent of more expensive scans.
What’s a healthy body-fat percentage?
Rough guides: women are often healthiest around 21–31% and men around 14–24%, with athletes lower. “Essential fat” (very low) can be unhealthy. Ranges vary with age.
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Educational use only. checkit.health calculators provide general information and are not a medical diagnosis or a substitute for professional advice. Always talk to a qualified healthcare professional about your health, symptoms or before making changes to medication, diet or exercise.
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