How to Calculate Body Mass Index BMI

Just about any fitness magazine has a body mass index chart, and just about any health or fitness website has a BMI calculator. However, if for some reason you want to calculate your own BMI, you can do it quite easily if you know your height and weight.

Things You'll Need

• Calculator

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Instructions

• 1

  Weigh yourself and jot down your weight in pounds. Find an accurate weight by weighing yourself first thing in the morning, before eating or getting dressed.

• 2

  Calculate your height in inches. For instance, if you are 5 feet, 7 inches, multiply 5 by 12, and add 7, for a total of 67 inches.

• 3

  Multiply your height in inches by itself, to get this number in units called "inches squared." Using the same example, a person 67 inches tall would calculate 67 in. x 67 in., for a result of 4,489 inches squared.

• 4

  Divide your weight in pounds by your height in inches squared: If you weigh 130, you would calculate it like this: 130 / 4,489 = 0.029

• 5

  Multiply that result by 703 to obtain your BMI. In this example, 0.029 x 703 = 20.4. This BMI falls in the normal range.