Body Fat Estimator.
Professional estimation of body composition using the US Navy tape-measure method.
Girth & Height Metrics
Clinical Composition Protocols
The US Navy Body Fat formula is widely recognized as the most accurate tape-measure based estimation method. It analyzes the relationship between your height and girth to differentiate between adipose tissue and lean mass.
Measurement Precision
Ensure measurements are taken against the skin, not over clothing. The waist measurement should be taken at the narrowest point for women and at the navel for men.
Metabolic Impact
Lean mass is metabolically active. Increasing your lean mass ratio significantly improves your resting metabolic rate (BMR).
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Body Fat Estimation Methodology.
The Calculation Branch
Industrial Standards.
The US Navy body fat formula, developed by Hodgdon and Beckett (1984), uses circumference measurements at the waist, hip (women), neck, and height. All measurements are taken at specific anatomical landmarks: waist at the narrowest point, hip at the widest point, neck just below the larynx. Measurements are in centimetres or inches.
In-Depth Analysis & Reference Data
Body fat percentage categories for adults: Essential fat (survival minimum) — men 2–5%, women 10–13%. Athletes — men 6–13%, women 14–20%. Fitness — men 14–17%, women 21–24%. Acceptable — men 18–24%, women 25–31%. Obese — men 25%+, women 32%+. The Navy method has an accuracy of approximately ±3–4% compared to DEXA scanning. It tends to overestimate body fat in very lean individuals and underestimate in those with unusual fat distribution.
Registry Questions & FAQ.
Is the US Navy method accurate?
The US Navy method correlates well with DEXA scanning for most body types, with an error margin of ±3–4%. It is less accurate for very muscular individuals (tends to overestimate fat) and very obese individuals. DEXA (dual-energy X-ray absorptiometry) is the gold standard but costs $50–$150 per scan. The Navy method is free, requires only a tape measure, and is accurate enough for tracking trends over time.
What is a healthy body fat percentage?
Health organizations generally consider body fat in the 'fitness' range healthy: 14–17% for men, 21–24% for women. The 'acceptable' range (18–24% men, 25–31% women) is associated with normal metabolic health for most adults. Body fat above 25% (men) or 32% (women) is associated with increased cardiovascular disease and metabolic syndrome risk.
Estimates for planning. Always confirm against an authoritative source.