Use this skinfold equation for a consistent field estimate when the correct three anatomical sites, sex-specific equation, caliper method, and units are used.

Sex used by the equation

Required string input.

Age (year)

Required number input.

Three protocol-specific skinfold measurements

Required list input.

Estimate body density and body-fat percentage from the sex-specific Jackson–Pollock three-site skinfold equation and Siri conversion. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Estimated body fat (%)

The resulting estimated body fat returned as a number.

Estimated body density (g/cm3)

The resulting estimated body density returned as a number.

• Skinfold estimates depend strongly on technician skill, site location, caliper, hydration, compressibility, age, sex, and similarity to the derivation population. They are not direct measurements or diagnoses.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Repeat measurements using a standardized protocol and trained measurer, track trends, and use a validated reference method when individual accuracy matters.

• Body Density to Body Fat Calculator

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