How to Calculate a Healthy BMI Range

BMI stands for "body mass index." It is a number that is calculated based on a person's height and weight, so it's different for everyone. However, what is true for everyone is the fact that a number in the healthy BMI range is an indicator of overall good health. People with too low or too high BMI numbers are generally underweight or overweight, predisposing them to a large number of health problems.

Things You'll Need

• Calculator
• Measuring tape

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Instructions

• 1

  Determine your weight. For an example, let's say we have a young woman who is 120 lbs.

• 2

  Measure your height. Let's say our young woman is 5-foot-5. All together, her height in inches equals 65. For this calculation, we need to square her height. This simply means taking the number and multiplying it by itself. So 65 squared equals 4,225.

• 3

  Divide your weight (remember, in pounds) by your height (in inches squared). For our example, we would take 120 divided by 4,225, which equals 0.029 (rounded).

• 4

  Take this number and multiply it by 703. 703 is the conversion factor we use to arrive at our BMI calculation. For our sample woman, we will take .029 (which was her weight divided by her squared height) and multiply that by 703, which equals 19.9.

• 5

  Consult the guidelines for a healthy BMI as assessed by the government's National Institutes of Health (see Resources below). Determine if your measurements fit into the range for a normal weight. You are considered underweight if your BMI is less than 18.5, normal if it's between 18.5 and 24.9, and overweight if your BMI is more than 25.