Age
Record in yearsThis is a recorded input rather than a body measurement site.
Enter your current age alongside the physical measurements.
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Method guide
Jackson & Pollock 7-Site Body Fat Calculator
Uses age plus skinfolds across the upper body, torso and thigh.
Calculate
- Accuracy
- ±3-4%Typical error against a reference method
- Equipment
- skinfold calipers
- Measurement count
- 8
Counts include age, weight and height when required.
How to measure
How to take the measurements
Equipment and Good Technique
Use skinfold calipers on bare, dry skin. Mark every landmark before starting. Grasp skin and the fat beneath it between thumb and forefinger, lift the fold away from the muscle, and keep holding it while the caliper jaws close slightly below your fingers. The jaws stay perpendicular to the fold even when the fold itself is diagonal.
Required Inputs and Measurement Locations
Measure every item listed for your calculation. Labels show when an input applies only to men or women.
Chest Skinfold
Record in mmOn the chest, between the armpit and nipple.
Fold direction: diagonal.
Mark the midpoint between the front of the armpit and nipple, then follow the natural diagonal fold.
Abdomen Skinfold
Record in mmOn the abdomen near the navel.
Fold direction: vertical.
Relax the abdomen, mark the same point beside the navel, and lift the fold away from the abdominal wall.
Thigh Skinfold
Record in mmOn the front of the thigh, halfway between the hip and knee.
Fold direction: vertical.
Unweight the measured leg, mark the midpoint, and lift the relaxed fold vertically.
Tricep Skinfold
Record in mmOn the back of the upper arm, halfway between the shoulder and elbow.
Fold direction: vertical.
Let the arm hang, mark the midpoint behind it, and lift vertically without tensing the triceps.
Subscapular Skinfold
Record in mmJust below the lower tip of the shoulder blade.
Fold direction: diagonal.
Find the blade tip by touch, mark immediately below it, and lift the fold diagonally.
Suprailiac Skinfold
Record in mmJust above the upper edge of the hip bone.
Fold direction: diagonal.
Find the hip bone’s upper edge, mark just above it, and follow the natural diagonal fold.
Midaxillary Skinfold
Record in mmOn the side of the torso, on the line descending from the middle of the armpit.
Fold direction: horizontal.
Mark the side line, lower the arm to relax the torso, and lift the fold horizontally.
Measurement Protocol
Follow this sequence
- Mark all sites on the right side before beginning, and arrange help for folds you cannot see or reach reliably.
- Follow one site order so the horizontal, vertical and diagonal folds are not confused as the session progresses.
- Take one reading at each marked site, waiting briefly before recording the caliper value.
- Rotate through the full sequence for repeat readings and pause if hand fatigue changes the pinch.
- Average only consistent readings; if they disagree, check the landmark, fold direction and caliper position before repeating.
Accuracy and mistakes
How accurate is the Jackson & Pollock 7-Site method?
Jackson & Pollock 7-Site has an estimated accuracy range of ±3–4% with proper technique. Use that range alongside the method’s practical limitations when deciding whether it suits your measurements.
Who it suits: Experienced caliper users, or pairs who can help one another reach and mark the rear and side sites.
The trade-off: The method covers more body regions, but it asks for a longer and more technically demanding measurement session.
What This Method Measures
Uses age plus skinfolds across the upper body, torso and thigh.
Jackson & Pollock 7-Site combines age with skinfolds across the arm, chest, side of the torso, back, abdomen and leg. Men and women follow the same site sequence.
It suits someone who is comfortable with calipers and wants the full protocol. The tradeoff is time and access: several folds are hard to see on yourself, and a longer sequence creates more opportunities to change pinch direction, landmark or caliper placement.
- Required inputs
- 8 per calculation.
- Equipment
- Prepare skinfold calipers.
Common mistakes that change the result
- Losing the midaxillary line when the arm returns to a relaxed position.
- Confusing the subscapular site below the shoulder blade with tissue directly over it.
- Switching fold direction while moving between horizontal, vertical and diagonal sites.
- Measuring every site once instead of rotating through repeat readings.
- Continuing after hand fatigue makes the pinch or caliper placement inconsistent.
What the estimate means
The calculator turns the recorded inputs into a body fat percentage estimate. For Jackson & Pollock 7-Site, the estimated accuracy range is ±3–4% with proper technique. A range is not a promise that one reading is exact.
Treat the result as an estimate. When tracking changes, compare readings collected with the same method and procedure. A changed tool, landmark, body side, timing or operator can make readings less comparable. The number does not diagnose health or replace qualified advice, and formulas with different inputs are not interchangeable.
How this compares to other methods
Ordered by typical error, lowest first. Counts include age, weight and height when required.
| Method | AccuracyTypical error against a reference method | Measurement count | Equipment |
|---|---|---|---|
| Parrillo | ±3-4% | 10 | skinfold calipers, a body-weight scale |
| Jackson & Pollock 7-SiteCurrent method | ±3-4% | 8 | skinfold calipers |
| Jackson & Pollock 4-Site | ±3.5-4.5% | 5 | skinfold calipers |
| Durnin & Womersley | ±3.5-5% | 5 | skinfold calipers |
| Jackson & Pollock 3-Site | ±4-5% | 4 | skinfold calipers |
| Covert Bailey | ±4-5% | 5 | a soft tape measure |
| U.S. Navy | ±4-6% | 3 for men · 4 for women | a soft tape measure, a reliable way to measure standing height |
| Modified YMCA | ±4-6% | 2 for men · 5 for women | a soft tape measure, a body-weight scale |
| YMCA | ±5-7% | 2 | a soft tape measure, a body-weight scale |
Where to Go Next
Read the evidence guide
Review the sources and limitations behind Jackson & Pollock 7-Site on its paired research page.
View research →Use the calculator app
Take your prepared readings to Body Fat Calculator, select Jackson & Pollock 7-Site, and enter the measurements listed for your calculation.
PRO+ includes measurement history and progress tracking in the app. You can also sync app results with Apple Health on iOS when you enable the integration and grant permission.
Get the app →