Body mass index, also known as BMI, is a calculation of your weight and your height to determine body fat levels. Healthcare workers commonly use it to identify individuals who may be overweight or obese. It’s important to understand that the BMI is a preliminary screening tool rather than a diagnosis. An actual diagnosis of obesity requires a healthcare worker to consider many factors in addition to your BMI. The World Health Organization, or WHO, provides weight classifications that use BMI values in metric units.
Step 1
Measure your weight in pounds with a bathroom scale. Divide your weight in pounds by 2.2 to obtain your weight in kilograms. Assume your weight is 146 lbs. for this example. Your weight is therefore 146 / 2.2 = 66.4kg.
Step 2
Measure your height in inches with a tape measure. Multiply your height in inches by 0.0254 to obtain your height in meters. Assume your height is 68 in. for this example. Your height is therefore 68 x 0.0254 = 1.73m.
Step 3
Calculate your BMI with the formula BMI = W / (H x H), such that W is your weight in kilograms and H is your height in meters. Assume your weight is 66.4kg and your height is 1.73m for this example. Your BMI is therefore 66.4 / (1.73 x 1.73) = 22.2.
Step 4
Determine your weight classification from your BMI. The WHO weight classification for BMI shows that a "normal" BMI is between 18.5 and 25, a BMI between 25 and 30 indicates pre-obesity and a BMI greater than 30 indicates obesity. The BMI of 22.2 in this example falls within the normal range.
Things You'll Need
- Bathroom scale
- Tape measure
- Calculator
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