Calculate Body Mass Index

Your body mass index can be calculated by entering your height and weight measurements into the BMI formula. BMI does not measure body fat directly but correlates closely to direct measures of fat in the body. The BMI formula can be used with the metric system or the English system. To determine your body mass index, simply plug the two measurements into the proper formula, and your BMI number will be the result of the equation.

Body Mass Index Information

Calculating Your Body Mass Index: An Overview

Research on obesity has shown that a person's level of body fat could be measured using a calculation called body mass index (BMI). BMI does not measure body fat directly but correlates closely to direct measures of body fat.

The only measurements needed to make a body mass index calculation are a person's height and weight. Because of the simplicity of BMI calculation guidelines, it is an inexpensive and easy tool for physicians and the general public to use as a way to screen for weight categories that may lead to health problems (see Health Effects of Obesity).

Specifics on How to Calculate Body Mass Index

BMI is calculated the same way for both adults and children. The BMI calculation is based on the following formula depending on whether you are using the metric system or the English system.

(Click on BMI Calculator to calculate body mass index.)

Metric System

When using the metric system to calculate body mass index, the BMI formula is weight in kilograms divided by height in meters squared (weight (kg) / [height (m)]²).

Since height is commonly measured in centimeters, divide height in centimeters by 100 to obtain height in meters before you use the formula.

To calculate BMI, take the weight (kg) and divide it by height (m). Then divide that number once again by height (m).

An example of calculating BMI: Height = 165 cm (1.65 m), Weight = 68 kg

BMI Calculation: 68 ÷ (1.65)² = 24.98

(Calculate Body Mass Index Continued: Page 2)