Calculator
Body fat percentage calculator from skinfolds
Use the 3-site or the 7-site protocol below: enter sex, age and the skinfolds in millimetres. Density comes from the Jackson and Pollock equations; body fat percentage from the Siri conversion.
Skinfolds: the 3-site protocol
Jackson and Pollock density
Density = a + b × Σ + c × Σ² + d × age, where Σ is the sum of the skinfolds in mm and age is in years.
| Sex | a | b | c | d |
|---|---|---|---|---|
| Men | 1.10938 | −0.0008267 | 0.0000016 | −0.0002574 |
| Women | 1.0994921 | −0.0009929 | 0.0000023 | −0.0001392 |
The formula
Body fat percentage (Siri) = 495 ÷ density − 450
Jackson & Pollock (1978); Jackson, Pollock & Ward (1980); Siri (1961). The equation estimates; it is not a clinical report and does not replace a direct measurement. It is the same calculation StatsCenter applies when a club collects.
Result
Skinfolds: the 7-site protocol
Jackson and Pollock density
Density = a + b × Σ + c × Σ² + d × age, where Σ is the sum of the skinfolds in mm and age is in years.
| Sex | a | b | c | d |
|---|---|---|---|---|
| Men | 1.112 | −0.00043499 | 0.00000055 | −0.00028826 |
| Women | 1.097 | −0.00046971 | 0.00000056 | −0.00012828 |
The formula
Body fat percentage (Siri) = 495 ÷ density − 450
Jackson & Pollock (1978); Jackson, Pollock & Ward (1980); Siri (1961). The equation estimates; it is not a clinical report and does not replace a direct measurement. It is the same calculation StatsCenter applies when a club collects.
Result
Collect your squad's skinfolds in StatsCenter.
The protocol comes ready, with its attempts, its formulas and every athlete's history.
No card needed, every module included. Sign-up and the product are in Portuguese.