Health
Body Surface Area (BSA) Calculator
Last updated: July 11, 2026
Calculate your body surface area in square meters using the Mosteller and Du Bois formulas. BSA is used for medical dosing and clinical assessments.
How to Use This BSA Calculator
- Select Metric (kg/cm) or Imperial (lbs/inches) units.
- Enter your weight and height.
- Click "Calculate BSA" to see results from both Mosteller and Du Bois formulas.
BSA Formulas
Mosteller: BSA (m²) = √[(height(cm) × weight(kg)) / 3600]
Du Bois: BSA (m²) = 0.007184 × height(cm)^0.725 × weight(kg)^0.425
BSA Reference Ranges
| Category | BSA (m²) |
|---|---|
| Child (average) | 0.8 – 1.1 |
| Adult female (average) | 1.4 – 1.7 |
| Adult male (average) | 1.6 – 2.0 |
| Athletes | 1.8 – 2.2+ |
Examples
Example: Average Adult
70 kg, 170 cm:
Mosteller: √[(170 × 70) / 3600] = √3.306 = 1.82 m²
Frequently Asked Questions
What is BSA used for?
BSA is widely used in medicine for drug dosing (especially chemotherapy), cardiac index calculation, and comparing physiological measurements across different body sizes. A typical adult BSA is 1.5–2.0 m².
Which BSA formula is more accurate?
Both Mosteller and Du Bois formulas are widely used. Mosteller is simpler and easier to calculate manually. Du Bois is considered slightly more accurate for very large or very small individuals. Most clinical settings accept either formula.