Body Fat Calculator
Enter your height and body measurements — neck and waist for men, plus hip for women — to estimate your body fat percentage using the U.S. Navy circumference method, along with a rough fitness category for your result.
How it works
This calculator uses the U.S. Navy circumference method, which estimates body fat percentage from your height plus a few tape-measure circumferences: neck and waist for men, and neck, waist, and hip for women. It's a simple formula based on the idea that these measurements correlate with body fat, not a direct measurement of fat itself.
Tip for accurate measurements
Measure your neck just below the larynx, your waist at the narrowest point (or at the navel), and — for the hip measurement — around the widest part of your hips. Keep the tape snug but not compressed, and measure a few times to get a consistent number.
Is this a medical measurement?
No — this is only an estimate based on a population-average formula, and it can be off by several percentage points depending on your body type. It's not a substitute for a clinical measurement like a DEXA scan, skinfold calipers, or bioelectrical impedance analysis, and it's not medical advice.
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