Jackson-Pollock 3-Site Caliper
The gold standard for accessible body fat tracking. Requires a high-quality skinfold caliper.
Estimated Body Fat
Body Density (Db)
The Mathematics
The JP3 formula calculates Body Density (Db) based on the sum of skinfolds (SS). It then runs Db through the Siri equation.
Male Db:1.10938 - (0.0008267 * SS) + (0.0000016 * SS^2) - (0.0002574 * Age)
Female Db:
1.0994921 - (0.0009929 * SS) + (0.0000023 * SS^2) - (0.0001392 * Age)
Siri Equation:
% Fat = (495 / Db) - 450