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    BMI and body surface area (BSA)

    Calculate body mass index (BMI) and body surface area (BSA, Mosteller).

    kg
    cm
    Enter values — the result appears instantly.

    For information only; not a substitute for medical advice. Data is neither sent nor stored.

    Formula

    BMI = weight (kg) / height (m)²; BSA (Mosteller) = √(height (cm) × weight (kg) / 3600).

    Reference ranges

    • < 18.5: underweight
    • 18.5–24.9: normal
    • 25–29.9: overweight
    • ≥ 30: obesity

    Frequently asked questions

    What is BSA used for?
    Body surface area is used for chemotherapy dosing and for normalizing certain laboratory and physiological parameters.