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Body Fat Calculator FullScreen

Use our calculator to estimate the body fat percentage of your body, using nothing but a tape measure and your keyboard. The calculator uses a basic formula developed by the U.S. Navy to calculate body fat percentage.


Body Fat Percentage (BFP) Formula

The Body Fat Calculator uses the following formulas to calculate the body fat percentage:

1. Imperial Units:

Male: BFP = 86.01 * [log10(A − N)] − 70.041 * [log10(H)] + 36.76

Female: BFP = 163.205 * [log10(W + C − N)] − 97.684 * [log10(H)] − 78.387

Where: BFP = Body Fat Percentage, A = Abdomen [in], C = Hip Circumference [in], H = Height [in], N = Neck [in], W = Waist [in]

2. Metric Units:

Male: BFP = 495 / ( 1.0324 − 0.19077 * [log10(W − N)] + 0.15456 * [log10(H)] ) − 450

Female: BFP = 495 / ( 1.29579 − 0.35004 * [log10(W + C − N)] + 0.221 * [log10(H)] ) − 450

Where: BFP = Body Fat Percentage, A = Abdomen [cm], C = Hip Circumference [cm], H = Height [cm], N = Neck [cm], W = Waist [cm]

What is Body Fat Calculator

A body fat calculator is a tool used to estimate the percentage of body fat in relation to total body weight. It provides an indication of the amount of fat tissue in the body as opposed to lean muscle mass, bone, and other tissues. Body fat percentage is often used as a measure of overall health and fitness. Here's how a body fat calculator typically works:

  1. Input Variables: To calculate body fat percentage, the calculator requires certain variables such as age, gender, height, weight, and sometimes additional measurements like waist, hip, or neck circumference.

  2. Calculation Method: There are various methods used to estimate body fat percentage, including simple formulas and more complex techniques. Commonly used methods include the Body Mass Index (BMI), skinfold calipers, bioelectrical impedance analysis (BIA), and dual-energy X-ray absorptiometry (DXA). Each method has its own mathematical formula or algorithm to determine body fat percentage.

  • BMI: Although not a direct measure of body fat, it calculates body fat indirectly based on height and weight. It divides weight in kilograms by the square of height in meters (BMI = weight / height^2) and categorizes individuals into different weight categories.

  • Skinfold Calipers: This method involves using calipers to measure the thickness of skinfold at specific body sites. The measurements are then plugged into an equation to estimate body fat percentage.

  • BIA: Bioelectrical impedance analysis uses a device that measures the resistance of electrical currents passing through the body. Fat tissues have higher resistance compared to lean tissues, and this information is used to estimate body fat percentage.

  • DXA: Dual-energy X-ray absorptiometry is a highly accurate method that uses X-ray technology to measure bone mineral density, lean tissue mass, and fat mass in different regions of the body.

  1. Interpretation: Once the body fat calculation is done, the calculator provides an estimate of the individual's body fat percentage. The interpretation of the results may vary depending on factors such as gender, age, and fitness levels. Generally, healthy body fat percentage ranges differ for males and females.

It is important to note that while body fat calculators can provide a rough estimation of body fat percentage, they are not as precise as more advanced laboratory methods. Factors like hydration levels, muscle mass, and distribution of fat can influence the accuracy of the results. It's always advisable to consult with a healthcare professional or fitness expert for a more comprehensive assessment of body composition and health.

Body Fat Calculator Example

Sure! Here's an example of using a body fat calculator to estimate body fat percentage:

Assume the following information for an individual:

Gender: Male Age: 30 years old Weight: 180 lbs Height: 6 feet (72 inches) Waist circumference: 32 inches Hip circumference: 40 inches

To calculate the body fat percentage, we can use the formula based on the U.S. Navy method:

  1. Calculate the lean body mass (LBM): LBM = (0.407 * weight in kg) + (0.267 * height in cm) - 19.2 = (0.407 * 180 lbs) + (0.267 * 72 inches) - 19.2 = 73.26 kg (rounded to two decimal places)

  2. Calculate the body fat mass: Body Fat Mass = Weight - Lean Body Mass = 180 lbs - (73.26 kg converted to lbs) = 180 lbs - 161.28 lbs = 18.72 lbs (rounded to two decimal places)

  3. Calculate the body fat percentage: Body Fat Percentage = (Body Fat Mass / Weight) * 100 = (18.72 lbs / 180 lbs) * 100 = 10.40% (rounded to two decimal places)

Therefore, the estimated body fat percentage for this individual would be approximately 10.40%.

Please note that this is just an example calculation using the U.S. Navy method, and various other methods and factors can be used to estimate body fat percentage, such as skinfold measurements or bioelectrical impedance analysis. It's always a good idea to consult with a healthcare professional or fitness expert for a more accurate assessment.