Body Fat Calculator
Estimate your body fat percentage using the US Navy circumference method. Enter your sex, height, and neck, waist (and hip for women) measurements.
How it works
The US Navy method estimates body density from body circumferences and height, then converts it to a body fat percentage. Measurements are entered in centimeters and converted to inches internally.
US Navy circumference formula (log₁₀-based)Worked examples
Male example
A 175 cm man with a 38 cm neck and 90 cm waist has an estimated body fat of about 14%.
Frequently asked questions
How accurate is the US Navy method?
It is a reasonable estimate (±3–5%) but not as precise as DEXA or hydrostatic weighing.
What is a healthy body fat percentage?
For men, roughly 14–24% is average; for women, roughly 21–31%.
Why do women need a hip measurement?
The female formula includes hip circumference because women store fat differently.
This tool is for general information only and is not medical advice. Always consult a qualified healthcare professional before making health-related decisions.
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