Body Mass Index (BMI) is a quick screening number that relates your weight to your height. It is widely used because it is simple to calculate and gives a rough sense of whether your weight is in a healthy range.
How BMI is calculated
BMI divides your weight in kilograms by the square of your height in metres. The standard categories are underweight (below 18.5), normal (18.5–24.9), overweight (25–29.9) and obese (30 and above).
Its limits
BMI does not distinguish muscle from fat, so very muscular people can register as “overweight” despite being healthy. It is a screening tool, not a diagnosis — always discuss health concerns with a professional.
Calculate your BMI
Enter your height and weight in metric or imperial units to get your BMI and category instantly, right in your browser.