Body Fat Percentage Calculator
Calculate your body fat percentage using the US Navy method and BMI-based formula
Your Measurements
Enter your measurements to calculate body fat
How to Measure
📍 Waist
Measure at the narrowest point, usually at the navel. Keep the tape horizontal and snug but not tight.
📍 Neck
Measure just below the larynx (Adam's apple). Keep head straight and look forward.
Methodology and Sources
US Navy Method
Developed by Hodgdon and Beckett at the Naval Health Research Center (1984). Uses circumference measurements of the neck, waist, and hip (for women) along with height to estimate body fat percentage. Widely used by the US military for fitness assessments.
Hodgdon, J.A. & Beckett, M.B. (1984). Prediction of percent body fat for U.S. Navy men and women from body circumferences and height. Naval Health Research Center, Report No. 84-29.
BMI-Based Method
Based on the Deurenberg equation, which estimates body fat percentage from Body Mass Index (BMI), age, and sex. This method is less accurate for muscular individuals but provides a useful estimate when circumference measurements are unavailable.
Deurenberg, P., Weststrate, J.A. & Seidell, J.C. (1991). Body mass index as a measure of body fatness. British Journal of Nutrition, 65(2), 105-114.
Formulas
US Navy (male): %BF = 495 / (1.0324 - 0.19077 * log10(waist - neck) + 0.15456 * log10(height)) - 450
BMI method (male): %BF = 1.2 * BMI + 0.23 * age - 16.2
Important Note
This calculator provides estimates based on circumference measurements. For the most accurate body fat measurement, consider DEXA scans, hydrostatic weighing, or professional calipers. Results may vary based on measurement accuracy and individual body composition.