Body Fat Calculator

How to Calculate Body Fat Percentage

Body fat percentage is a measure of fitness level that calculates the amount of body fat in your body as a percentage of your total body weight. Understanding how to calculate body fat percentage can help you assess your overall health and fitness.

U.S. Navy Method

This calculator uses the U.S. Navy Method to estimate body fat percentage. This method is based on body circumference measurements and height.

Body Fat Percentage Formulas

The formulas used to calculate body fat percentage differ for males and females:

For Males:

$$BF\% = 86.010 \times \log_{10}(abdomen - neck) - 70.041 \times \log_{10}(height) + 36.76$$

For Females:

$$BF\% = 163.205 \times \log_{10}(waist + hip - neck) - 97.684 \times \log_{10}(height) - 78.387$$

Where:

• BF% is Body Fat Percentage
• All measurements are in centimeters

Calculation Steps

1. Measure your height in centimeters
2. Measure your neck circumference at the narrowest point
3. Measure your waist circumference at the navel for men, or at the narrowest point for women
4. For women, measure your hip circumference at the widest point
5. Input these measurements into the appropriate formula based on your gender
6. Calculate to get your estimated body fat percentage

Example Calculation

Let's calculate the body fat percentage for a male who is 180 cm tall, with a neck circumference of 38 cm and a waist circumference of 85 cm:

Step 1: Apply the formula

$$\begin{align} BF\% &= 86.010 \times \log_{10}(85 - 38) - 70.041 \times \log_{10}(180) + 36.76 \end{align}$$

Step 2: Calculate

$$\begin{align} BF\% &= 86.010 \times \log_{10}(47) - 70.041 \times \log_{10}(180) + 36.76 \\ &= 86.010 \times 1.6721 - 70.041 \times 2.2553 + 36.76 \\ &= 143.81 - 157.96 + 36.76 \\ &= 22.61 \end{align}$$

Step 3: Final result

The calculated body fat percentage is 22.61%, which falls within the "Average" category for males.

Visual Representation

This bar chart illustrates the calculated body fat percentage (22.61%) in comparison to the standard body fat percentage categories for males: Essential Fat (2-5%), Athletes (6-13%), Fitness (14-17%), Average (18-24%), and Obese (25% and above).