BMI calculator
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BMI is a reference for adults — it does not apply to pregnant women, muscular athletes, the elderly or children. Use it as screening; a real assessment comes from a health professional.
How to use
Frequently asked questions
Weight divided by height squared (kg/m²). E.g.: 80 kg and 1.75 m → 80 ÷ (1.75 × 1.75) = 26.1. The calculator does the math as you type and shows the classification.
Below 18.5: underweight · 18.5–24.9: normal · 25–29.9: overweight · 30–34.9: obesity class I · 35–39.9: class II · 40+: class III. The calculator highlights your range and the healthy weight span for your height.
It is a reference for adults. It does not work well for pregnant women, very muscular athletes, the elderly or children. Use it as screening — a real assessment comes from a health professional.