Body fat percentage (US Navy method)
Body fat percentage from neck, waist, and hip circumferences. Validated against hydrostatic weighing.
About this calculator
The US Navy method estimates body fat percentage from anthropometry. Developed by Hodgdon and Beckett (Naval Health Research Center, 1984). Used by US Navy for personnel screening since 1981. Formulas. Men: %BF = 86.010 × log10(waist – neck) – 70.041 × log10(height) + 36.76. Women: %BF = 163.205 × log10(waist + hip – neck) – 97.684 × log10(height) – 78.387. Measurements in centimeters; waist at umbilicus, neck below the larynx, hip at the widest point. Health ranges (American Council on Exercise). Men: <6% – essential, 6-13% – athlete, 14-17% – fitness, 18-24% – acceptable, >=25% – obese. Women: <14% – essential, 14-20% – athlete, 21-24% – fitness, 25-31% – acceptable, >=32% – obese. Reference ranges are 3-5% higher in older adults. Clinical use. Adjunct to BMI for body composition. Particularly useful in athletes and patients with high muscle mass where BMI overestimates risk. Used in sports medicine, cardiology for visceral obesity monitoring, endocrinology in metabolic syndrome. Limitations. Estimation with 3-5% error compared to DEXA (gold standard). Does not capture fat distribution – two patients with the same %BF can have different cardiovascular risk depending on visceral fat. Not used in pregnancy or with marked edema. For precise assessment – DEXA, high-grade bioimpedance, or BodPod.
Source
Formula version: hodgdon-beckett-1984-v1
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