How to Calculate Body Fat for Free

Your body fat percentage is often a better indicator of overall health than your weight alone. To determine how much body fat you have, you will calculate your Body Mass Index (BMI), which is based on your weight and height. It can determine whether you are underweight, at a normal weight, overweight or obese. The calculation is an estimation, but it is a useful tool to assess your health.

Things You'll Need

• Tape measure
• Digital scale
• Calculator

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Instructions

• 1

  Have someone help with the measuring tape if necessary.

  Measure your height with the tape measure, standing tall against a wall for best results. To calculate your height in inches, multiply the feet by 12 and add the remaining inches. For instance, if you are 5' 11" then you are 71 inches tall ((5 x 12) + 7).

• 2

  Take off your shoes before weighing yourself.

  Weigh yourself on the scale. Include one digit after the decimal point (181.2 rather than 181) for greater accuracy.

• 3

  Multiply your height in inches by itself (71 x 71 = 5,041) and write this number down or remember it.

• 4

  Multiply your weight by 703 (181.2 x 703 = 127,383.6).

• 5

  Divide the second number (your weight multiplied by 703) by the first number (your height squared). For example, 127,383.6 ÷ 5,041 = 25.26. This number is your body fat percentage.