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BMI Calculator

Body mass index, category and the healthy weight range for your height.

Your result appears here

Fill in the fields on the left and press Calculate. The answer, the breakdown and a copy button all land in this card.

How it is calculated

BMI = weight (kg) ÷ height (m)²

Categories follow the WHO scale: under 18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, 30 and above obese.

Worked example

70 kg at 170 cm gives 70 ÷ (1.70 × 1.70) = 24.2, which sits in the normal range. The healthy weight band for that height is 53.5–72.0 kg.

Questions people ask

It is a screening number, not a diagnosis. It cannot tell muscle from fat, so athletes often read as overweight, and it is interpreted differently for children, pregnant women and older adults.

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