Skinfold Body Fat Calculator
Calculate body fat percentage using skinfold caliper measurements. Choose between the Jackson-Pollock 3-site or 7-site protocol for accurate results.
Measure each site in millimeters (mm). Take 3 measurements at each site and enter the average.
Enter all 7 skinfold measurements in millimeters (mm).
Measurement Site Guide
📍 Skinfold Measurement Sites
- Chest: Diagonal fold between armpit and nipple (men) or collarbone and armpit (women)
- Abdomen: Vertical fold 1 inch (2.5 cm) right of the navel
- Thigh: Vertical fold on the front of the thigh, midway between hip and knee
- Tricep: Vertical fold on the back of the upper arm, midway between shoulder and elbow
- Subscapular: Diagonal fold below the shoulder blade
- Suprailiac: Diagonal fold above the hip bone
- Midaxillary: Vertical fold on the side of the torso at armpit level
Formulas Used
Chest: 12mm, Abdomen: 18mm, Thigh: 15mm
Sum = 45mm
Body Density = 1.10938 − (0.0008267 × 45) + (0.0000016 × 45²) − (0.0002574 × 30)
Body Density ≈ 1.0662
Body Fat = (495 ÷ 1.0662) − 450 ≈ 14.3%
Frequently Asked Questions
With proper technique, skinfold tests have an error margin of ±3-4%. Accuracy improves with experienced testers and quality calipers. Consistency matters more than absolute accuracy for tracking changes.
The 7-site test is more comprehensive and may be slightly more accurate. The 3-site test is quicker and sufficient for most purposes, especially for tracking changes over time.
Lange or Harpenden calipers are gold-standard but expensive. Slim Guide and Accu-Measure are affordable alternatives with good accuracy when used correctly.
Measure at consistent times—ideally in the morning, before exercise, and when normally hydrated. Avoid measuring after workouts or sauna use.