Body Surface Area (BSA) Calculator
Your BSA from height and weight, two formulas
AI logs your meals from a photo. Diet & workouts in one app.Get the free appBody Surface Area (BSA) Calculator
Body surface area (BSA) is the total surface area of the human body and is often a more accurate basis than weight for medication dosing — especially chemotherapy — and for indexing physiological measures like cardiac output. This calculator estimates BSA from your height and weight using the two most common equations, Mosteller (the simple square-root formula) and Du Bois, and shows their average. It is for information only; clinical dosing must be confirmed by a healthcare professional.
Body surface area (BSA) is widely used in medicine to dose chemotherapy and other drugs and to index cardiac output. This is an estimate — clinical decisions should always be made by a healthcare professional.
Frequently Asked Questions
- What is body surface area (BSA)?
- BSA is the total external surface area of the body, measured in square metres. It is widely used in medicine to scale drug doses, especially chemotherapy, and to express physiological values like cardiac index, since it tracks body size better than weight alone.
- How is BSA calculated?
- The Mosteller formula is BSA (m2) = the square root of (height cm x weight kg / 3600), a simple, widely used estimate. The Du Bois formula uses height and weight with exponents. Enter both measurements and the tool returns each result plus the average.
- What is a typical BSA value?
- The average adult BSA is about 1.7 m2, with most adults falling roughly between 1.5 and 2.0 m2 depending on height and weight. Different formulas can vary slightly, so clinical dosing usually specifies which formula to use.