Body Surface Area Calculator
Calculate body surface area (BSA) using the Mosteller formula — used in drug dosing and oncology.
How to use this tool
- Enter weight and height in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your body surface area and the full breakdown beneath it.
Body surface area (BSA) is used in drug dosing, especially chemotherapy. The Mosteller formula is BSA = √(height_cm × weight_kg ÷ 3600).
Frequently asked questions
- What is the Mosteller formula?
- BSA (m²) = √(height in cm × weight in kg ÷ 3600). It is simple and accurate enough for most clinical purposes.
- Why is BSA used for drug dosing?
- BSA correlates better with organ size and cardiac output than weight alone, making it the preferred scaling factor for chemotherapy and many IV medications.