How to Calculate BMI

BMI Calculator

 
  English    Metric
lbs.
ft. in.

What is BMI

BMI stands for Body Mass Index. It is the measure of relative weight based on a person's mass and height. It is used as a simple method to assess how much a person's body weight is, compared to what is normal or desirable for a person of his or her height. BMI provides a reasonable estimate of body fat, for most people. However, this measurement does not consider other factors such as bone or muscle mass. So if you are athletic, mascular or has high bone density, your BMI might not be reliable. So it is recommended to use your BMI result together with other methods to test for body fat.

BMI Categories

To find out your BMI, use the BMI calculator above and compare the result to the table below.

BMIWeight Status
Below 18.5Underweight
18.5 to 24.9Normal
25.0 to 29.9Overweight
30 or higherObese

Calculations

There are two ways to measure BMI, the English and the Metric system. The English system uses pounds for the weight and inches for the height. The Metic system on the other hand uses kilogram for the weight and meters for the height.

Formulas

English System :

(a ÷ (b)²) x 703 = BMI

Where:
a = weight in pounds
b = height in inches
703 = conversion factor to change units from metric to imperial

Metric System :
a ÷ (b)² = BMI

Where:
a = weight in kilograms
b = height in meters


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