The BMI Calculator works out your Body Mass Index — a simple number that compares your weight to your height and gives a quick sense of whether you are in a healthy range. BMI = weight (kg) ÷ height (m)².

What the colours mean

The gauge follows the World Health Organization adult categories: Underweight below 18.5, Normal 18.5–24.9 (the green, healthy zone), Overweight 25–29.9, and Obese 30 and above. The needle points to your value so you can see your zone at a glance.

Asian-Indian cut-offs

People of South Asian descent tend to carry more body fat at a given BMI, so health risks begin earlier. Tick Asian-Indian cut-offs to use the recommended lower thresholds — overweight from 23 and obese from 25.

Important limits of BMI

BMI is a useful guide, not a diagnosis. It does not separate muscle from fat, so very muscular people can read as “overweight”, while it can underestimate fat in older adults. It is not designed for children, pregnant women, or athletes. For anything important, talk to a doctor. Nothing you enter is uploaded — the calculation runs entirely in your browser.