How to Calculate Body Fat with the Jackson-Pollock 3 Body Fat Formula

The Jackson-Pollock 3-site body fat test, developed by researchers Dr. Andrew Jackson and M. L. Pollock, is one of the most widely used caliper-based methods for estimating body fat percentage. It requires only three skinfold measurements, a body weight reading, and the subject's age and gender.

This method is popular because of its simplicity. All you need is a set of skinfold calipers, a bathroom scale, and a few minutes. No specialized training is required, and the measurements can be performed solo for most sites, though a partner improves accuracy.

For a complete overview of all body fat measurement methods and how to use calipers, see our guide to measuring body fat.

Who Is This Method For?

The Jackson-Pollock 3-site method is a good fit for most people of average build who want a quick, accessible body fat estimate. It is one of the fastest caliper-based formulas to perform and does not require reaching difficult anatomical landmarks.

However, this method tends to underestimate body fat in very lean individuals, including bodybuilders and performance athletes. If you fall into that category, consider the Yuhasz method (designed for athletes) or the Jackson-Pollock 7-site method (more measurement sites for improved accuracy).

Skinfold Measurement Locations

The Jackson-Pollock 3-site formula uses different measurement sites for males and females to account for gender-specific fat distribution patterns.

Male Measurement Sites

Site	Location	Fold Direction
Chest (Pectoral)	Halfway between the nipple and the upper portion of the pectoral muscle near the armpit	Diagonal
Abdomen	One inch to the right of the belly button	Vertical
Thigh	Halfway between the kneecap (patella) and the inguinal crease (where the top of the thigh meets the hip)	Vertical

Female Measurement Sites

Site	Location	Fold Direction
Tricep	Halfway between the top of the shoulder and the elbow, on the back of the arm	Vertical
Suprailiac	Above the superior anterior iliac crest (the upper and forward protrusion of the hip bone)	Diagonal
Thigh	Halfway between the kneecap (patella) and the inguinal crease (where the top of the thigh meets the hip)	Vertical

Jackson-Pollock 3-Site Formula for Males

Measure the following skinfolds in millimeters with body fat calipers: Chest (Pectoral), Abdomen, and Thigh.

Step	Formula
Body Density	1.10938 - (0.0008267 x sum of skinfolds) + (0.0000016 x sum of skinfolds²) - (0.0002574 x age)
Body Fat %	(495 / Body Density) - 450

Jackson-Pollock 3-Site Formula for Females

Measure the following skinfolds in millimeters with body fat calipers: Tricep, Suprailiac, and Thigh.

Step	Formula
Body Density	1.0994921 - (0.0009929 x sum of skinfolds) + (0.0000023 x sum of skinfolds²) - (0.0001392 x age)
Body Fat %	(495 / Body Density) - 450

Example Calculation

Here is a worked example for a 30-year-old male with the following skinfold measurements:

Site	Measurement
Chest	12 mm
Abdomen	18 mm
Thigh	15 mm
Sum of Skinfolds	45 mm

Step 1: Calculate Body Density

Body Density = 1.10938 - (0.0008267 x 45) + (0.0000016 x 45²) - (0.0002574 x 30)

Body Density = 1.10938 - 0.037202 + 0.00324 - 0.007722

Body Density = 1.067696

Step 2: Convert to Body Fat Percentage

Body Fat % = (495 / 1.067696) - 450

Body Fat % = 463.53 - 450

Body Fat % = 13.6%

Tips for Accurate Results

Measure at the same time of day. Morning measurements before eating produce the most consistent results. Hydration, meals, and exercise all affect skinfold thickness.

Take each measurement twice. If the two readings at a site differ by more than 2 mm, take a third and average the two closest. Rotate through all three sites before going back to remeasure, giving the skin time to return to its normal thickness.

Always measure from the right side. The Jackson-Pollock formulas were developed using right-side measurements. Switching sides introduces inconsistency.

Use the same calipers every time. Different caliper brands apply different jaw pressures, so results are not directly comparable across brands.

Track monthly. Body fat changes gradually. Monthly measurements provide meaningful data. Weekly or daily measurements mostly capture noise from hydration and glycogen fluctuations.

How the JP 3-Site Compares to Other Methods

Method	Sites	Best For
JP 3-Site (this article)	3	Quick estimate, beginners, solo measurement
JP 4-Site	4	Same sites for both genders, slightly more accurate
JP 7-Site	7	Most comprehensive JP method
Durnin-Womersley	4	Broad age range (16-72), clinical use
Yuhasz	6	Athletes and highly fit individuals
Parillo	9	Most detailed caliper method

Supporting Your Body Composition Goals

Tracking your body fat gives you a baseline. Pairing that data with the right nutritional support helps you act on it.

FitProbio+ features HOWARU Shape Bifidobacterium animalis subsp. lactis B420, a probiotic strain shown to assist with healthy body composition by supporting gut barrier function and promoting less calorie consumption. Each capsule is delivered in DRcaps gastro-resistant capsules and sealed in nitrogen-purged blister packs for stability.

Conclusion

The Jackson-Pollock 3-site method is one of the fastest and most accessible ways to estimate body fat with calipers. Three measurements, a simple formula, and minimal equipment. For most people of average build, it provides a reliable way to track body composition changes over time when performed consistently.

If you find that three sites do not capture enough detail, or if you are leaner and more trained than the general population, step up to the JP 4-site or JP 7-site method for improved accuracy.