BMI Calculator


BMI Index

Body mass index (BMI) is a measure of body fat based on height and weight that applies to adult men and women. It is widely used as a common indicator of whether a person has a healthy body weight for their height. The value obtained from the calculation of BMI is used to categorize whether a person is underweight, normal weight, overweight, or obese depending on the range in which it falls.

BMI Formula

The formula used for calculating the BMI index in (kg/m2) is given below:

BMI(kg/m2) = mass(kg) / height2(m)

Alternatively, it can also be expressed as:

BMI(kg/m2) = mass(lb) / height2(in) × 703

BMI Category

BMI RangeBMI CategoryBMI Sub-Category
< 16UnderweightSevere Thinness
16 - 17Moderate Thinness
17 - 18.5Mild Thinness
18.5 - 25NormalNormal
25 - 30OverweightOverweight
30 - 35ObeseObese Class I
35 - 40Obese Class II
> 40Obese Class III

BMI chart for adults

This is a graph of BMI categories Based on the World Health Organization data, . The dashed lines represent subdivisions within a major categorization.

BMI Chart