BSA Calculator
Calculate Body Surface Area — used in medical dosage calculations.
Input Values
kg
cm
Results
Enter values to see results.
⚠️ Results are indicative only. Consult a qualified professional before making any decisions.
What is this Calculator?
The BSA (Body Surface Area) Calculator computes the total surface area of the human body in m² using the Mosteller formula. BSA is used in medicine to calculate drug dosages, especially in chemotherapy, and to assess cardiac output and kidney function.
How to Use
1
Enter Weight: Enter your body weight in kilograms.
2
Enter Height: Enter your height in centimetres.
3
View Results: See your Body Surface Area in m².
Frequently Asked Questions
BSA is used in medicine to calculate drug dosages (especially for chemotherapy, where toxicity is more accurately predicted by BSA than by weight alone), and to assess cardiac index, kidney function, and burn area.
We use the Mosteller formula: BSA (m²) = √(Height(cm) × Weight(kg) ÷ 3600). It is the most widely used formula due to its simplicity and good accuracy.
The average BSA for an adult is approximately 1.73 m² — this is often used as a reference value in clinical studies when individual BSA is not available.
BMI measures weight relative to height (a 2D measure), while BSA estimates the actual surface area of the body in m² (a 3D measure). BSA is more useful for medical dosing purposes.
Other BSA formulas include DuBois & DuBois (1916), Haycock (1978), Gehan & George (1970), and Fujimoto (1968). They give slightly different results but all are within a narrow range for adults.
BSA is simply a measurement, not a health indicator like BMI. It is a neutral value used for clinical calculations — neither higher nor lower is inherently better or worse.