Estimates body fat percentage from a few tape measurements, using the U.S. Navy circumference method. An estimate based on a standard formula — not a diagnosis or a clinical measurement.
Getting an accurate estimate depends on measuring in the right place, the right way.
Measure just below the larynx (Adam's apple), with the tape sloping slightly downward toward the front of the neck.
Measure at the navel, keeping the tape horizontal and snug against the skin without pulling it tight enough to compress it.
Measure at the widest point around the hips and buttocks, with the tape parallel to the floor.
Standing height without shoes, measured against a flat wall.
Quick answers to the questions people ask most about this method.
It's a body fat estimation method developed by Hodgdon and Beckett in 1984, using height and a small number of circumference measurements — neck and waist for men, and neck, waist, and hip for women — in place of more involved lab methods.
It's an estimate, not a direct measurement. Compared to reference methods like DEXA scans or hydrostatic weighing, the circumference method typically has a margin of error of about 3-4 percentage points, and accuracy depends heavily on measuring at the correct location and keeping the tape snug but not compressed.
Neck: measure just below the larynx, with the tape sloping slightly downward at the front. Waist: measure at the navel. Hip (women only): measure at the widest point around the hips and buttocks. Keep the tape parallel to the floor and snug against the skin without compressing it.
The original research fit separate regression equations for men and women because fat distribution patterns differ by sex, and the female equation additionally accounts for hip circumference, which isn't part of the male equation.