US Navy method body-fat percentage from neck, waist and hip measurements, with category rating.
Men: 495 ÷ (1.0324 − 0.19077×log10(waist−neck) + 0.15456×log10(height)) − 450 · Women use hip in place of part of the equation
A man at 180 cm with 95 cm waist and 38 cm neck lands near 20% body fat.
Keep the tape level and snug without compressing skin. Measure the neck below the larynx, the waist at the navel (men) or narrowest point (women), and the hips at their widest point.
Essential fat is roughly 2–5% for men and 10–13% for women. Athletes commonly sit around 6–13% (men) and 14–20% (women); 'acceptable' spans up to about 24% and 31% respectively.
Within about 3–4% of lab methods like DEXA for most people — good for tracking trends even if the absolute number is imperfect.
The female formula accounts for fat distribution patterns that differ on average from men's.
Body Mass Index in metric or imperial units, with WHO category and healthy weight range for your height.
Estimate your 1RM from a rep max set, plus percentage-based training loads.
Basal Metabolic Rate via the Mifflin-St Jeor equation — the calories your body burns at complete rest.
Total Daily Energy Expenditure: your full-day calorie burn based on BMR and activity level.
Daily calorie targets for losing, maintaining or gaining weight based on your goal pace.
Healthy weight ranges from four classic formulas plus the normal-BMI band for your height.