Body Surface Area (BSA) Calculator
Mosteller (Recommended)
DuBois and DuBois
Haycock
Boyd
Total Body Surface Area
0.00
Square Meters (m²)
What is Body Surface Area (BSA)?
Body Surface Area (BSA) is the measured or calculated surface area of a human body. In clinical medicine, BSA is often considered a more accurate indicator of metabolic mass than body weight because it is less affected by abnormal adipose tissue (body fat).
Why is BSA Important?
Medical professionals use BSA for several critical clinical purposes, including:
- Dosage Calculation: Determining the correct dose for highly toxic drugs, such as chemotherapy or narrow-therapeutic-index medications.
- Cardiac Index: Relating the cardiac output to the size of the individual.
- Renal Function: Normalizing Glomerular Filtration Rate (GFR) to compare kidney function between individuals of different sizes.
- Fluid Replacement: Calculating fluid requirements for burn victims using the Parkland formula.
Common Formulas Used
While several formulas exist, the Mosteller formula is the most widely used due to its simplicity and accuracy.
Mosteller Formula: BSA = √([Height(cm) × Weight(kg)] / 3600)
DuBois Formula: BSA = 0.007184 × Weight(kg)0.425 × Height(cm)0.725
Example Calculation
If an adult male weighs 80 kg and stands 180 cm tall, the calculation using the Mosteller formula would be:
1. Multiply height and weight: 80 × 180 = 14,400
2. Divide by 3600: 14,400 / 3600 = 4
3. Take the square root: √4 = 2.00 m²
Average BSA Values
Typical BSA values vary by age and biological sex:
- Neonates (Newborns): 0.25 m²
- Child (9 years): 1.07 m²
- Adult Women: 1.6 m²
- Adult Men: 1.9 m²