How to Calculate Adult BMI

The Centers for Disease Control and Prevention (CDC) identifies the body mass index, or BMI, as a "fairly reliable indicator" of a person's level of body fat. The formula uses your height and weight to determine if you are overweight. On the BMI scale, the CDC projects a result between 18.5 and 24.9 to be normal for both adult men and adult women. Higher BMI values suggest you may be overweight, which puts you at a higher risk for various diseases including stroke, hypertension and type 2 diabetes.

Things You'll Need

• Calculator

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Instructions

• 1

  Convert your height to inches by multiplying the number of feet by 12 and adding the number of inches. For example, if you stand five feet six inches tall, you would multiply five by 12 to get 60, and then add six to get 66 inches.

• 2

  Multiply your height in inches by itself. In this example, you would multiply 66 by 66 to get 4,356.

• 3

  Divide your weight in pounds by the result from step 2. Continuing the example, if you weigh 170 pounds, you would divide 170 by 4,356 to get 0.03902663.

• 4

  Multiply the result from step 3 by 703 to calculate your BMI. Finishing the example, you would multiply 0.03902663 by 703 to get about 27.4.