How to Calculate Your BMI Online

Body Mass Index (BMI) is one way to assess whether your weight poses a health risk. A simple calculation determines how much body fat you have, which can then be used to determine your risk for heart disease, high blood pressure, diabetes and other health concerns. BMI is a measure of whether you are the right weight in relation to your height. Calculate BMI by dividing your weight by the square of your height. For a hassle-free way to find your BMI, use one of the various sources online providing a BMI calculator.

Things You'll Need

• Tape Measure
• Weighing Scale

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Instructions

• 1

  Know your measurements. Measure your height and weight. Most online BMI calculators offer metric and imperial conversions.

• 2

  Select a BMI calculator. Use a search engine to find an "online BMI calculator." Alternatively, the National Institutes of Health offers a simple to use BMI calculator (see first reference).

• 3

  Enter your measurements to calculate your BMI.

• 4

  Know what your BMI means. A range from 18.5 to 24.9 is the recommended BMI, the National Institutes of Health states. A score of 18.5 or less indicates you are underweight while a score of 25 or more suggests you are overweight. A person is considered obese with a score of 30 or more.

• 5

  Know the limitations. BMI does not consider body composition. A weightlifter, for example, will be heavy in proportion to his height. That means his BMI likely will suggest he is overweight.