BMI Calculator
Body Mass Index with WHO category and healthy weight range.
About this tool
BMI is a screening measure of weight relative to height. It uses the WHO categories, which are widely used by clinicians to flag people who may benefit from a closer look at metabolic health.
BMI does not measure body composition — very muscular people may register a high BMI without excess fat. For most adults it remains a useful, simple starting point.
Source: World Health Organization BMI classification.
Frequently asked questions
Why is BMI used if it isn't perfect?
It's simple, free, and a strong population-level predictor of cardiometabolic risk. For an individual, waist circumference and waist-to-hip ratio add useful information.
What if I'm very athletic?
Muscle mass can push BMI up. Pair BMI with waist circumference (<94 cm men / <80 cm women is reassuring).
Is BMI different for Asian populations?
Yes — South Asian and East Asian populations have higher diabetes risk at lower BMI. A threshold of 23 (overweight) and 27.5 (obesity) is sometimes used.
⚕️ Educational only — not a substitute for professional medical advice, diagnosis, or treatment. In an emergency call your local emergency services.