Free OnlineCalculators & Converters
Body Fat Calculator
Estimate your body fat percentage using the US Navy method with body measurements. Shows fat mass, lean mass, and body fat category.
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US Navy Method — measure at the widest points
Key Features — Body Fat Calculator
US Navy body fat formula
Separate male and female formulas
Body fat categories (essential to obese)
Fat mass and lean mass calculation
Metric and imperial measurements
Why Use This Tool — Body Fat Calculator
Free Online Body fat calculatorBody fat percentage calculator — for EveryoneFast & Easy Navy body fat calculatorBody fat measurement — 100% FreeFree Online Body composition calculator
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Frequently Asked Questions — Body Fat Calculator
How accurate is the Navy body fat formula?
The US Navy method is reasonably accurate for most people, with an error margin of about 3–4% compared to DEXA scan (the gold standard). It tends to be less accurate at the extremes — very lean or very obese individuals — but is a solid free estimate without equipment.
Where exactly do I measure?
Neck: measure at the mid-neck, below the larynx. Waist: measure at the navel (belly button) level. Hips (women only): measure at the widest point of the hips and buttocks. Use a flexible tape measure and take measurements in the morning without clothing for best accuracy.
What body fat percentage is considered healthy?
For men, essential fat is 2–5%, athletic 6–13%, fitness 14–17%, average 18–24%, obese 25%+. For women, essential is 10–13%, athletic 14–20%, fitness 21–24%, average 25–31%, obese 32%+. Women naturally carry more essential fat due to hormonal and reproductive functions.