Estimate your body fat percentage using the U.S. Navy circumference method. Enter your neck, waist, and hip measurements to get an accurate body fat estimate.
Measure neck at its narrowest point, waist at the navel. Uses the U.S. Navy circumference method.
The U.S. Navy body fat method estimates body composition using simple tape measurements — no calipers or DEXA scan required. It calculates body fat percentage from neck, waist, and hip circumferences relative to height, using a validated logarithmic formula.
Formula: U.S. Navy: 495 / (1.0324 − 0.19077 × log10(waist − neck) + 0.15456 × log10(height)) − 450
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