Find your Body Mass Index instantly. Works for metric and imperial units.
BMI, or Body Mass Index, is a simple calculation that uses your height and weight to estimate whether you have a healthy body weight. It was developed in the 1800s by Adolphe Quetelet and remains one of the most widely used screening tools in clinical practice.
BMI does not measure body fat directly. Two people with the same BMI can have very different body compositions. Athletes, for instance, often have higher BMIs due to muscle mass.
The formula is: BMI = weight (kg) divided by height (m) squared. In imperial units: BMI = (weight in pounds × 703) divided by (height in inches squared).
BMI does not account for age, sex, ethnicity, or where fat is stored in the body. It's a starting point, not a definitive health measure. Pairing BMI with waist circumference and other assessments gives a more complete picture.