Slaughter Skinfold Body Fat Calculator (Children)

About this calculator

The Slaughter skinfold equations, published in 1988, are the standard pediatric method for estimating body fat percentage in children and adolescents ages 8-17 from just two skinfold measurements — triceps and calf — measured with skinfold calipers. The equations differ by sex and use a different formula depending on whether the sum of the two skinfolds is above or below 35 mm, since fat distribution and skinfold-compressibility patterns change as kids move through puberty.

Pediatric exercise physiologists, school and youth-sports fitness testing programs, and pediatric researchers use Slaughter rather than adult skinfold equations (like Jackson-Pollock) because adult formulas are calibrated on fully-grown bodies and don't account for the different fat patterning of a growing child. The result is typically reported alongside an age- and sex-appropriate healthy range, since "healthy" body fat percentage for a 10-year-old is not the same target used for an adult.

This calculator takes a child's triceps and calf skinfold measurements plus age and sex and returns an estimated body fat percentage and category.