BMI (Body Mass Index) Calculator
Calculate your Body Mass Index and see where it falls on the standard WHO reference scale.
How BMI is calculated
BMI divides weight by height squared (kg / m² metrically, or 703 × lb / in² in imperial units). It was designed in the 1830s by Adolphe Quetelet as a population-level statistic, not an individual diagnostic tool — which is the root of most of the criticism it gets today.
Where it breaks down
BMI can't distinguish muscle from fat. A muscular athlete and a sedentary person of the same height and weight get an identical BMI, despite very different body compositions, and the scale doesn't separately account for age, sex, or fat distribution.