Skinfold Body Fat Calculator (Jackson-Pollock 3-Site)
Body fat from 3-site skinfold measurements.
Enter your values
Choose one of: Male, Female.
Enter the site 1 fold in mm.
Enter the site 2 fold in mm.
Enter the site 3 fold in mm.
Enter the age in years.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Body density
- 1.0733
- Estimated body fat
- 11.2%
Quick answer
The Jackson-Pollock 3-site formula converts skinfold thickness and age into an estimated body density and body fat percentage.
Body density = c1 - c2 x (sum of folds) + c3 x (sum)^2 - c4 x age; %BF = 495/BD - 450
At a glance
| What it does | Body fat from 3-site skinfold measurements. |
|---|---|
| Category | Health |
| Inputs needed | Sex, Site 1 fold, Site 2 fold, Site 3 fold, Age |
| Main output | Body density |
| Formula | Body density = c1 - c2 x (sum of folds) + c3 x (sum)^2 - c4 x age; %BF = 495/BD - 450 |
| Cost | Free — no sign-up, no download |
How to use the Skinfold Body Fat Calculator (Jackson-Pollock 3-Site)
- 1Take three skinfold measurements with calipers at the standard sites (chest, abdomen, thigh for men; tricep, suprailiac, thigh for women).
- 2Enter the sum and your age.
- 3Caliper technique matters a lot — inconsistent pinching is the biggest source of error, and this is not a diagnostic measurement.
Inputs explained
- Sex
- Choose one of: Male, Female.
- Site 1 fold(mm)
- Enter the site 1 fold in mm.
- Site 2 fold(mm)
- Enter the site 2 fold in mm.
- Site 3 fold(mm)
- Enter the site 3 fold in mm.
- Age(years)
- Enter the age in years.
Worked example
Using the values the calculator loads with:
Inputs
- SexMale
- Site 1 fold12 mm
- Site 2 fold15 mm
- Site 3 fold10 mm
- Age30 years
Results
- Body density1.0733
- Estimated body fat11.2%
Frequently asked questions
Why three sites and not seven?
The 3-site protocol is faster and correlates well with the more detailed 7-site version.
Can I do this myself?
It's easier and more repeatable with a second person taking the measurements.
What do I need to enter into the Skinfold Body Fat Calculator (Jackson-Pollock 3-Site)?
Just 5 values: sex, site 1 fold, site 2 fold, site 3 fold, age. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Skinfold Body Fat Calculator (Jackson-Pollock 3-Site) work out the answer?
The Jackson-Pollock 3-site formula converts skinfold thickness and age into an estimated body density and body fat percentage. It applies the formula Body density = c1 - c2 x (sum of folds) + c3 x (sum)^2 - c4 x age; %BF = 495/BD - 450 and shows the working so you can check each step by hand.
Is the Skinfold Body Fat Calculator (Jackson-Pollock 3-Site) free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.