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Determining Your Body Mass Index

What is body mass index?

Determining how much you should weigh is not a simple matter of looking at an insurance height-weight chart, but includes considering the amount of bone, muscle, and fat in your body's composition. The amount of fat is the critical measurement.

A good indicator of how much fat you carry is the Body Mass Index (BMI). Although it is not a perfect measure, it gives a fairly accurate assessment of how much of your body is composed of fat.

Calculate your BMI using the English formula

BMI can be calculated using pounds and inches:

BMI = (weight in pounds x 703) / (height in inches x height in inches)

For example, a person who weighs 165 pounds and is 5 feet 4 inches tall has a BMI of 28.

(165 lbs x 703) / (64 inches x 64 inches) = 28

Calculate your BMI using the metric formula

BMI can be calculated using kilograms and meters:

BMI = weight in kilograms / (height in meters x height in meters)

For example, a person who weighs 99.79 kilograms and is 1.905 meters tall has a BMI of 27.5.

99.79 kg / (1.905 meters x 1.905 meters) = 27.5

A BMI between 25 and 29 is considered overweight. Anything over 30 is considered obese.