Body Fat Percentage Calculator
NewEstimate body fat percentage using the U.S. Navy circumference method — neck, waist (and hip for women), and height measurements, no calipers or scan required.
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estimated body fat (U.S. Navy method)
Frequently Asked Questions
How does the U.S. Navy method estimate body fat without a scan?
It uses a logarithmic formula derived from circumference measurements (neck, waist, and for women, hips) relative to height. The Navy developed and validated this formula as a practical field-expedient alternative to hydrostatic weighing for fitness assessments.
How accurate is this compared to a DEXA scan or calipers?
It's a reasonable estimate (typically within a few percentage points for most body types) but less precise than DEXA scans or skinfold calipers administered by a trained professional — treat the result as a general estimate, not a clinical measurement.
Why does the formula need a hip measurement for women but not men?
The Navy method uses separate formulas for each sex, since typical body fat distribution differs between men and women — the female formula was found to need the hip measurement to maintain accuracy, while the male formula doesn't.
What should I measure exactly for "waist" and "neck"?
Waist is typically measured at the navel level (not the narrowest point), and neck is measured just below the larynx — measuring at inconsistent points is the most common source of inaccurate results with this method.
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