Jackson-Pollock skinfold calculator (3, 4 and 7 sites)

Choose the protocol and enter sex, age, weight and the skinfolds measured with calipers. The calculator shows body fat percentage, body density, fat mass and lean mass.

years
lb
To calculate fat and lean mass
Skinfolds
mm
mm
mm
Body fat
14.2%
Sum of skinfolds: 47 mm
Body density
Converted to % body fat with the Siri equation
1.0663 g/cm³
Fat mass
24.4 lb
Lean mass
147.6 lb

Estimate for adults. Always use the same protocol and assessor to compare assessments.

How it works

  1. 3 sites — men: chest, abdomen and thigh; women: triceps, suprailiac and thigh (Jackson & Pollock, 1978; Jackson, Pollock & Ward, 1980).
  2. 7 sites: chest, midaxillary, triceps, subscapular, abdomen, suprailiac and thigh.
  3. For the 3 and 7-site protocols, the equation estimates body density, converted to % body fat with the Siri equation (1961).
  4. The 4-site protocol (triceps, abdomen, suprailiac and thigh) estimates % body fat directly.

FAQ

Which protocol should I use: 3, 4 or 7 sites?

The 7-site protocol tends to be more stable because it covers more areas; the 3-site one is quicker. What matters most is using the same protocol with the same client so you can compare progress.

Which side of the body should I measure?

By convention, the right side, with the client standing and relaxed. Take two or three readings per site and use the average.

In Trainer Fácil, every assessment is saved to the client's profile so you can compare progress month by month.

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