Body Fat Calculator
Estimate body-fat percentage from tape measurements — no calipers needed.
Formula
About this calculator
Body-fat percentage tells you something BMI cannot: how much of your weight is actually fat versus muscle, bone and water. Two people at the same BMI can have very different body compositions, which is why athletes often look "overweight" on BMI despite being lean. This calculator estimates body fat using the U.S. Navy circumference method — a well-validated, no-equipment alternative to skinfold calipers or DEXA scans.
The method needs only a tape measure. For men it uses height, neck and waist; for women it adds the hip measurement. Measure with a snug, level tape: the waist at the navel for men or the narrowest point for women, the neck just below the larynx, and the hips at their widest point. Enter the numbers and the calculator returns your body-fat percentage, a fitness category, and — if you add your weight — your fat mass and lean mass in the same units.
The categories follow the American Council on Exercise ranges, which differ by sex because women naturally carry more essential fat. Tape methods typically land within a few percent of clinical measurements, which is accurate enough to track progress over time. For the most reliable trend, measure at the same time of day under the same conditions and watch the direction of change rather than fixating on a single reading.
Frequently asked questions
How does the Navy body-fat method work?
It applies a published formula to circumference measurements — neck and waist for men, plus hips for women — together with height. It estimates body fat without calipers or lab equipment.
How accurate is it?
The tape method is generally within a few percentage points of clinical measurements like DEXA for most people. It is more useful for tracking change over time than for a single exact figure.
What is a healthy body-fat percentage?
Ranges differ by sex. For men, roughly 14–17% is fitness level and 18–24% is average; for women, about 21–24% is fitness and 25–31% is average. Essential fat is higher in women.
How should I take the measurements?
Use a snug, level tape. Measure the waist at the navel (men) or narrowest point (women), the neck below the larynx, and the hips at the widest point. Measure under consistent conditions each time.
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⚠️ Body-fat estimates are for general information only and are not medical advice. Consult a healthcare or fitness professional for a full assessment.