Body Surface Area (BSA) Calculator
Calculate body surface area (BSA) with the Mosteller and Du Bois medical formulas.
Fill in your details, then check your personalized result and recommendations.
Formula
Mosteller: BSA = √(height·cm × weight·kg ÷ 3600)
Worked example
180 cm, 80 kg → 2.0 m²
What the body surface area calculator does
Body surface area (BSA) is the total external area of the human body, expressed in square metres. It is widely used in medicine — for calculating drug dosages, particularly in chemotherapy, and for estimating metabolic and cardiac parameters. This calculator computes BSA using two of the most established formulas.
How the formulas work
The Mosteller formula, valued for its simplicity, takes the square root of height in centimetres multiplied by weight in kilograms, divided by 3,600. The Du Bois formula, published in 1916, uses a power equation and is the classic clinical reference. Both produce similar results for most adults, which is why this tool shows both.
How to interpret your result
BSA increases with both height and weight, and the average adult value is around 1.7 m². Clinicians prefer BSA over body weight for certain calculations because it correlates better with metabolic rate and organ function. The two formulas typically agree closely; small differences are normal.
Health recommendations
This calculator is intended for general information. Medication dosing and any clinical decisions based on BSA should always be performed by qualified healthcare professionals using validated tools and the patient's full clinical picture.
FAQ
+What is body surface area used for?
BSA is used clinically to dose medications (especially chemotherapy) and assess metabolic needs.
+Which BSA formula is most common?
Mosteller is widely used for its simplicity; Du Bois is the historical standard.
+What is an average BSA?
Around 1.7 m² for adults, varying with height and weight.