How to Calculate Body Surface Area
What is Body Surface Area?
Body Surface Area (BSA) is the measured or calculated surface of a human body. It is used in clinical medicine primarily for calculating chemotherapy dosages, cardiac index, and burn surface area. BSA is more accurate than weight alone for drug dosing because it correlates better with metabolic rate.
Formula
- BSA
- √(height × weight / 3600) — √(height × weight / 3600)
Step-by-Step Guide
- 1DuBois & DuBois (1916): BSA = 0.007184 × height^0.725 × weight^0.425
- 2Mosteller (1987): BSA = √(height × weight / 3600)
- 3Height in cm, weight in kg; BSA in m²
- 4Average adult BSA: 1.73 m² (used as reference in eGFR)
Worked Examples
Frequently Asked Questions
What is Bsa?
Body Surface Area (BSA) is the measured or calculated surface of a human body. It is used in clinical medicine primarily for calculating chemotherapy dosages, cardiac index, and burn surface area
How accurate is the Bsa calculator?
The calculator uses the standard published formula for bsa. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.
What units does the Bsa calculator use?
This calculator works with kilograms, centimetres, inches, square metres. You can enter values in the units shown — the calculator handles all conversions internally.
What formula does the Bsa calculator use?
The core formula is: DuBois & DuBois (1916): BSA = 0.007184 × height^0.725 × weight^0.425. Each step in the calculation is shown so you can verify the result manually.
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