How to Compute for Your Body Mass Index

An average bathroom scale can be used to determine whether or not someone is overweight, but body mass index is a more accurate indicator. The body mass index of a person estimates their total body fat, and clearly presents it in the form of a number that shows whether the person is underweight, normal, overweight or obese. Body mass index is very easy to calculate.

Things You'll Need

• Bathroom scale
• Measuring tape
• Body mass index chart

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Instructions

• 1

  Weigh yourself on a bathroom scale to get a base idea of what you weigh. Any properly calibrated bathroom scale will work, but a digital scale will give you a more accurate reading.

• 2

  Measure your height while standing tall against a flat wall. Use a measuring tape for the most accurate reading. A ruler or yardstick will be prone to errors, and not as accurate as a measuring tape.

• 3

  Divide the height calculation by itself to get its square root number. Use inches if you live in the United States, or meters if you live in a country that uses the metric system.

• 4

  Divide your weight by the square number of your height that you calculated. Record your weight in pounds if you live in the United States, or in kilograms for countries that use the metric system.

• 5

  Multiply the result by 703 if you recorded your weight and height in pounds and inches. The number that results is your calculated body mass index.

• 6

  Use a a body mass index chart to determine what your status is. An ideal result will be between 18.5 and 25. Consult your doctor if the resulting number is higher or lower than what is listed as a healthy result on the body mass index chart. A doctor will be able to further test for health issues that may be affecting your body mass index results.