Skinfold Body Fat Calculator
Estimate body fat using skinfold measurements.
Accurate Measurements Required
Enter measurements to see results.
Skinfold analysis is a common and relatively inexpensive method for estimating body fat percentage. It involves using a special tool called a skinfold caliper to measure the thickness of a double layer of skin and the underlying subcutaneous fat at specific sites on the body. This calculator uses the **Jackson and Pollock 3-site formula**, one of the most widely recognized skinfold equations, to estimate your body composition.
The Principle Behind Skinfold Measurement
The core assumption of skinfold analysis is that the amount of fat stored just under the skin (subcutaneous fat) is directly proportional to the total amount of body fat. By measuring the thickness of this subcutaneous fat at several key locations, it's possible to use regression equations to predict overall body density.
The Jackson/Pollock 3-Site Formula
This method is popular because it requires measuring only three sites, making it quicker than more extensive methods. The sites are different for men and women to account for typical differences in fat distribution patterns.
Measurement Sites for Men:
- Chest: A diagonal fold taken halfway between the nipple and the armpit crease.
- Abdomen: A vertical fold taken about 2 cm (1 inch) to the side of the navel.
- Thigh: A vertical fold taken on the front of the thigh, midway between the hip and the knee.
Measurement Sites for Women:
- Tricep: A vertical fold on the back of the upper arm, halfway between the shoulder and the elbow.
- Suprailiac: A diagonal fold taken just above the crest of the hip bone.
- Thigh: A vertical fold taken on the front of the thigh, midway between the hip and the knee.
From Skinfolds to Body Fat Percentage
The calculation is a two-step process:
- Calculate Body Density: The sum of the three skinfold measurements (in mm) and the person's age are plugged into a specific formula to estimate body density.
- Calculate Body Fat Percentage: Once body density is known, the Siri equation is commonly used to convert it into a body fat percentage:
Body Fat % = (495 / Body Density) - 450
Keys to Accuracy
The accuracy of this method is highly dependent on the skill of the person taking the measurements. For reliable results:
- Use a high-quality skinfold caliper.
- Ensure the measurements are taken at the precise anatomical locations.
- Pinch the skinfold firmly with the thumb and index finger.
- Place the caliper jaws perpendicular to the fold, about 1 cm away from your fingers.
- Release the caliper lever and read the measurement to the nearest 0.5 mm.
- Take multiple measurements at each site and use the average to reduce error.
When performed correctly by a trained individual, the skinfold method can be a very accurate and practical way to track changes in body composition over time.
Disclaimer: This calculator provides an estimation based on the data you enter. For the most accurate results, skinfold measurements should be taken by a trained fitness professional or healthcare provider.
Enter values to see the results.
Skinfold analysis is a common and relatively inexpensive method for estimating body fat percentage. It involves using a special tool called a skinfold caliper to measure the thickness of a double layer of skin and the underlying subcutaneous fat at specific sites on the body. This calculator uses the **Jackson and Pollock 3-site formula**, one of the most widely recognized skinfold equations, to estimate your body composition.
The Principle Behind Skinfold Measurement
The core assumption of skinfold analysis is that the amount of fat stored just under the skin (subcutaneous fat) is directly proportional to the total amount of body fat. By measuring the thickness of this subcutaneous fat at several key locations, it's possible to use regression equations to predict overall body density.
The Jackson/Pollock 3-Site Formula
This method is popular because it requires measuring only three sites, making it quicker than more extensive methods. The sites are different for men and women to account for typical differences in fat distribution patterns.
Measurement Sites for Men:
- Chest: A diagonal fold taken halfway between the nipple and the armpit crease.
- Abdomen: A vertical fold taken about 2 cm (1 inch) to the side of the navel.
- Thigh: A vertical fold taken on the front of the thigh, midway between the hip and the knee.
Measurement Sites for Women:
- Tricep: A vertical fold on the back of the upper arm, halfway between the shoulder and the elbow.
- Suprailiac: A diagonal fold taken just above the crest of the hip bone.
- Thigh: A vertical fold taken on the front of the thigh, midway between the hip and the knee.
From Skinfolds to Body Fat Percentage
The calculation is a two-step process:
- Calculate Body Density: The sum of the three skinfold measurements (in mm) and the person's age are plugged into a specific formula to estimate body density.
- Calculate Body Fat Percentage: Once body density is known, the Siri equation is commonly used to convert it into a body fat percentage:
Body Fat % = (495 / Body Density) - 450
Keys to Accuracy
The accuracy of this method is highly dependent on the skill of the person taking the measurements. For reliable results:
- Use a high-quality skinfold caliper.
- Ensure the measurements are taken at the precise anatomical locations.
- Pinch the skinfold firmly with the thumb and index finger.
- Place the caliper jaws perpendicular to the fold, about 1 cm away from your fingers.
- Release the caliper lever and read the measurement to the nearest 0.5 mm.
- Take multiple measurements at each site and use the average to reduce error.
When performed correctly by a trained individual, the skinfold method can be a very accurate and practical way to track changes in body composition over time.
Disclaimer: This calculator provides an estimation based on the data you enter. For the most accurate results, skinfold measurements should be taken by a trained fitness professional or healthcare provider.