Body Fat Percentage Calculator

Estimate body fat percentage using the U.S. Navy circumference method.

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What This Calculator Does

Estimate body fat percentage using the U.S. Navy circumference method.

It combines Sex, Height, Waist Circumference, Neck Circumference to estimate Estimated Body Fat, Fat Mass, Lean Mass.

Formula & Method

Core equations: U.S. Navy method (example male): BF\%=86.010\log_{10}(waist-neck)-70.041\log_{10}(height)+36.76. Female variant uses hip term.

Notation used in the formulas: R = Estimated Body Fat; x_{1} = Sex; x_{2} = Height; x_{3} = Waist Circumference; x_{4} = Neck Circumference; x_{5} = Hip Circumference (female only); x_{6} = Weight.

Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.

Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.

Inputs Used

Sex: Used directly in the calculation.
Height: Used directly in the calculation.
Waist Circumference: Used directly in the calculation.
Neck Circumference: Used directly in the calculation.
Hip Circumference (female only): Used directly in the calculation.
Weight: Used directly in the calculation.

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