Body Mass Index (BMI) is a method of indirectly determining how much body fat you have. It can help you determine what “weight category” you are in by comparing your weight and height against other people of different weights and heights.

To calculate your BMI, simply plug your weight and height into the calculator below. The calculator will take this information, run it through a mathematical formula, and assign you a number. This number is your BMI score. Once you have your score compare it to the following chart to determine what weight category you fall in:

• Less than 18—Underweight
• 18-25—Normal weight
• 25-29—Overweight
• Above 30—Obese

Keep in mind that the BMI is not always a 100% accurate indicator of your weight category by itself. It is based on what medical health professionals consider “normal.”

But as we all know, not all bodies are “normal.” Take somebody like Shaquille O’Neal for example. At 7’1” and 325 pounds, Shaq’s BMI is 31.6, which puts him in the “obese” category. But Shaquille O’Neal is far from being obese. He simply doesn’t have what most people would call a “normal” body.

Don’t fall into immediate despair if your BMI is high. It doesn’t automatically mean you are overweight or obese. However, it is a good indicator in most cases, and if your BMI is high you should seriously consider what this may mean and seek further medical assistance from your doctor or nutritionist.