How to Figure BMI for Adults

The body mass index (BMI) is an easy-to-use internationally recognized guide that compares your weight with your height to indicate whether you are underweight, overweight or a healthy weight for your size. If you are overweight, it's advisable to speak to a health care professional about ways to get back into shape. The National Heart Lung and Blood Institute warns that BMI is not always an accurate indicator of health, however, as those with a lot of muscle will have a high BMI but should not necessarily be considered obese.

Things You'll Need

• Bathroom scales
• Yardstick
• Calculator (optional)

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Instructions

Calculate Your BMI

• 1

  Get someone to help you measure your height with a yardstick. Record your height in inches.

• 2

  Weigh yourself and record your weight in pounds.

• 3

  Square your weight in inches (multiply weight in inches by weight in inches). Write down the number.

• 4

  Divide your weight in pounds by the number you obtained in step 3.

• 5

  Multiply your answer by 703. This is your BMI.

Interpret Your BMI

• 6

  You are seen to have a healthy weight if your BMI is between 19 and 24.9.

• 7

  You are regarded as overweight if your BMI is between 25 and 29.9.

• 8

  Your are seen as obese if your BMI is 30 or more.