Body Surface Area Calculator
Clinical Pharmacology & Cardiology Indexing
Body Surface Area Calculator
Compute patient BSA across five medical formulas side-by-side. Calculate Cardiac Index and standardized kidney filtration parameters (GFR).
Scenarios:
Patient Anthropometrics
cm
kg
Hemodynamics & Renal (Optional)
L/min
mL/min
Clinical Pharmacology Notice
Body Surface Area modeling helps standardize medications with narrow therapeutic windows (e.g. chemotherapy). Mosteller represents the general clinical default. For pediatrics, Haycock is historically preferred.
Average Body Surface Area (BSA)
1.849
m²Formula Variance
0.5%
Standardized Cardiac Index
2.7 L/min/m²
✔ Normal perfusion range
Standard GFR Index
84.2 mL/min/1.73m²
Normalized baseline clearance
Patient Physiology Report
Patient height is 175 cm and weight is 70 kg. The computed average BSA is 1.849 m². This aligns with adult clinical dosing criteria.
Scientific BSA Formulations Side-by-Side
| Formula | Computed BSA | Target Demographics & Standard Use |
|---|---|---|
| Mosteller | 1.845 m² | Standard clinical default. Standardized for general use. Preferred |
| DuBois & DuBois | 1.848 m² | Historic baseline. Tends to underestimate in pediatric populations. |
| Haycock | 1.847 m² | Clinically preferred for infants, children, and neonates. |
| Gehan & George | 1.854 m² | Adaptable for extreme tall statured demographics. |
| Boyd | 1.851 m² | Accounts for varying tissue densities in cachectic or low mass patient profiles. |
Frequently Asked Questions
Why is BSA preferred over body weight for chemotherapy dosing?▾
Chemotherapeutic agents have very narrow margins between therapeutic effectiveness and toxic levels. Studies show that systemic clearances and distributions of these drugs scale far more linearly with total vascular surface area (represented by BSA) than with raw body weight. Using weight alone would over-dose obese patients and under-dose tall/lean patients.
What is the clinical significance of a GFR standard index?▾
Standard GFR represents absolute kidney clearance rates. Standardizing kidney function to an average body size of 1.73 m² allows doctors to quickly check if clearance capacities are normal (typically > 90 mL/min/1.73m²) without having to adjust benchmarks for a small child or extremely large adult manually.
What is a normal Cardiac Index range?▾
The Cardiac Index normalizes cardiac output to body size. A healthy cardiac index ranges from 2.5 to 4.0 L/min/m². Values below 2.0 typically indicate cardiogenic shock or insufficient circulatory perfusion.