The Body Surface Area (BSA) Calculator estimates the total surface area of the human body in square meters — a value commonly used in medicine for drug dosing (especially chemotherapy), physiological scaling, and clinical assessments. This widget offers the Mosteller formula (simple and commonly recommended) and the classical DuBois formula for comparison. Enter weight in kilograms and height in centimeters, choose a formula (or show both), and the calculator returns BSA to three decimal places. Results are approximate; use clinical guidance when BSA is used for medical dosing or treatment decisions.