📏 Body Surface Area (BSA) Calculator

Estimate your body surface area (BSA) using two common formulas: DuBois and Mosteller. Enter your height and weight to calculate your BSA in square meters (m²).

Note: BSA is widely used for medication dosing and medical assessments, but it should not replace professional medical advice.

Understanding Body Surface Area (BSA)

Body Surface Area (BSA) is the measure of the external surface of the human body. It is used in medicine for tasks such as calculating drug dosages, determining metabolic rate, and assessing cardiac index. BSA provides a more accurate reflection of metabolic mass than body weight alone, because it is less affected by abnormal adipose mass.

Common BSA Formulas

  • DuBois Formula (1916): BSA = 0.007184 × Height(cm)0.725 × Weight(kg)0.425
  • Mosteller Formula (1987): BSA = √((Height(cm) × Weight(kg)) ÷ 3600)

Applications of BSA

  • Calculating chemotherapy and other drug dosages
  • Normalizing physiological parameters such as GFR (glomerular filtration rate)
  • Estimating metabolic rate and cardiac index

Limitations

BSA does not distinguish between lean body mass and fat mass. Formulas may be less accurate in extremely obese or underweight individuals, children, and the elderly.

Frequently Asked Questions (FAQs)

What is Body Surface Area (BSA)?
BSA is the total external surface area of the human body. It is used in medical settings for dosing medications and assessing physiological functions.
Which formula is most accurate?
Mosteller and DuBois are widely used. Mosteller is simpler and often preferred clinically, while DuBois is historically important and still referenced.
Why is BSA important in medicine?
BSA helps determine appropriate medication dosages, especially for drugs with narrow therapeutic ranges like chemotherapy agents.
Can BSA be used for children?
Yes, BSA is commonly used in pediatrics for medication dosing, but formulas should be applied carefully, and professional guidelines followed.
Is BSA better than BMI?
BSA and BMI measure different things. BMI reflects weight relative to height, while BSA estimates body surface area. Both are useful depending on context.