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BMI Calculator

Body Mass Index from height and weight (metric). For general screening only — not medical advice.

BMI formula

Body Mass Index is BMI = weight(kg) ÷ height(m)². So for 70 kg at 1.75 m: 70 ÷ (1.75 × 1.75) = 22.9.

BMI categories (WHO)

BMICategory
Below 18.5Underweight
18.5 – 24.9Healthy weight
25.0 – 29.9Overweight
30.0 and aboveObese

Limitations

BMI does not distinguish muscle from fat, so athletes can score "overweight" while being lean. It is a population screening tool, not a diagnosis. For body composition try the body fat calculator.

FAQ

Is BMI different for men and women?

The formula and adult categories are the same. Body-fat distribution differs, which is why BMI is only a rough guide.

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