BMI Calculator

Calculate adult body mass index and understand the range.

How it’s calculated

Body mass index compares weight to height. Adult categories follow the World Health Organization.

BMI = weight(kg) ÷ height(m)².
Under 18.5 underweight · 18.5–24.9 healthy · 25–29.9 overweight · 30+ obese.

Source: World Health Organization, Obesity and overweight fact sheet.

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