Body Surface Area Calculator

Body Surface Area (BSA): Understanding DuBois and Mosteller Formulas for Medical Applications

Body Surface Area (BSA) is a measure of the total surface area of the human body, commonly used in medical practice to calculate drug dosages, chemotherapy regimens, and fluid requirements. BSA provides a more accurate dosing metric than body weight alone, especially for medications with narrow therapeutic windows. The two most commonly used formulas are the DuBois formula and the Mosteller formula, each with specific applications in clinical settings.

DuBois Formula: The DuBois formula, developed in 1916, calculates BSA as: BSA = 0.007184 × (Height in cm)^0.725 × (Weight in kg)^0.425. This formula is widely used in clinical practice and research, particularly for chemotherapy dosing and pediatric medicine. It's considered more accurate for adults but may overestimate BSA in very tall or very short individuals.

Mosteller Formula: The Mosteller formula, developed in 1987, is simpler and easier to calculate: BSA = √[(Height in cm × Weight in kg) / 3600]. This formula is commonly used in emergency medicine and when quick calculations are needed. It's generally accurate for most adults and children, making it a practical alternative to the DuBois formula in many clinical settings.

Medical Relevance and Drug Dosage: BSA is crucial for calculating chemotherapy drug dosages, where precise dosing is critical for treatment efficacy and safety. Many chemotherapy protocols specify drug doses in mg/m² (milligrams per square meter of BSA). BSA is also used for calculating fluid resuscitation volumes, burn injury assessment, and determining appropriate medication doses in pediatric patients where weight-based dosing may be less accurate.

⚠️ Important Disclaimer: This calculator provides BSA calculations for informational and educational purposes only. It is not medical advice and should not be used for actual medical treatment, drug dosing, or clinical decision-making. BSA calculations for medical purposes must be performed by qualified healthcare professionals who consider individual patient factors, medical history, and clinical context. Always consult with licensed healthcare providers for medical advice, drug dosing, and treatment decisions. Do not use this calculator to self-medicate or adjust prescribed dosages.

Clinical Applications: Healthcare professionals use BSA for various purposes including chemotherapy dosing (most common application), calculating cardiac index and other hemodynamic parameters, determining appropriate fluid replacement volumes, assessing burn injury extent, and pediatric medication dosing. Our calculator supports both DuBois and Mosteller formulas, allowing you to compare results and understand the differences between these calculation methods.