Doctor use BMI Number to judge illness. Body fat level is a major factor to tell about our health issues risk. But how do we know whether our body fat level is normal or not. Here is a solution for this problem. BMI Calculator is a tool which calculates your Body Mass Index i.e. BMI according to height and weight. It tells you about the category of fat level you fall in. The categories of fat level are as follows: 1. Underweight : Need to gain weight. 2. Normal Weight : Healt