Body Fat Calculator (Skinfold)

The Jackson & Pollock 3-site method is a widely used skinfold protocol that estimates body fat percentage from three specific caliper measurement sites. For men, the sites are chest, abdominal, and thigh. For women, they are tricep, suprailiac, and thigh. These measurements are entered into a validated regression equation to calculate body density and body fat percentage.

When performed correctly by a trained professional, skinfold calipers can estimate body fat within ±3–4% of more precise methods like DEXA scans. Accuracy depends heavily on consistent measurement technique, caliper quality, and the tester's experience. Self-measurement can increase error, so having a trainer or technician take the readings is recommended.

Use a quality skinfold caliper and pinch the skin firmly between your thumb and forefinger, pulling it away from the muscle. Apply the caliper about 1 cm below your fingers and read the value after 1–2 seconds. Take each measurement at least twice and average the results. Always measure on the right side of the body.

For males, this calculator uses the chest, abdominal, and thigh sites. For females, it uses the tricep, suprailiac, and thigh sites. These site combinations are the standard 3-site protocol defined by Jackson and Pollock (1978, 1980).

Classifications typically range from 'Essential Fat' (the minimum needed for survival) through 'Athletes', 'Fitness', 'Average', and 'Obese'. These categories help contextualize your result relative to health and fitness norms. The exact ranges differ between men and women due to physiological differences in essential fat storage.

For men, a healthy body fat range is generally considered to be 8–19%, with athletes typically falling between 6–13%. For women, 21–33% is generally healthy, with athletes ranging from 14–20%. Values below these ranges can indicate essential fat deficiency, while values above may increase health risks.

This calculator requires skinfold caliper measurements, so you'll need a pair of calipers to use it accurately. Basic plastic calipers are available inexpensively online and provide reasonable accuracy when used properly. If you don't have calipers, consider a different method such as a BMI or waist-to-height ratio calculator as an alternative estimate.

For tracking fitness progress, measuring every 4–8 weeks is typically sufficient. More frequent measurements may not reflect true changes due to day-to-day variation from hydration, food intake, and measurement technique. Always measure under similar conditions (e.g., same time of day, same tester) for the most consistent results.