Body Surface Area Calculator
Calculate BSA using the Mosteller formula for medical dosing
Patient Information
BSA Results
Body Surface Area
1.87
m²
Height:
170 cm
Weight:
70 kg
Formula:
Mosteller
BSA Categories
Low: < 1.7 m²
Normal: 1.7-2.0 m²
High: > 2.0 m²
Clinical Applications
Common Medical Uses
| Application | Calculation | Value | Reference |
|---|---|---|---|
| Chemotherapy Dosing | Drug dose × BSA | - | Varies by protocol |
| Renal Function | GFR adjustment | - | 1.73 m² standard |
| Fluid Requirements | Maintenance fluids | - | 1500-2000 mL/m²/24h |
| Cardiac Index | CI = CO / BSA | - | 2.5-4.0 L/min/m² |
About Body Surface Area (BSA)
Body Surface Area (BSA) is a measurement of the total surface area of the human body. It is used in many medical settings, particularly for determining medication dosages and calculating medical indicators.
Mosteller Formula:
BSA (m²) = √( [Height(cm) × Weight(kg)] / 3600 )
BSA (m²) = √( [Height(in) × Weight(lb)] / 3131 )
Other BSA Formulas:
- Du Bois formula: BSA = 0.007184 × Height(cm)0.725 × Weight(kg)0.425
- Haycock formula: BSA = 0.024265 × Height(cm)0.3964 × Weight(kg)0.5378
- Gehan and George formula: BSA = 0.0235 × Height(cm)0.42246 × Weight(kg)0.51456
- Boyd formula: BSA = 0.0003207 × Height(cm)0.3 × Weight(grams)(0.7285 - (0.0188 × log(weight))
Clinical Applications of BSA:
- Chemotherapy dosing: Most cytotoxic drugs are dosed according to BSA
- Renal function assessment: Glomerular filtration rate (GFR) is often normalized to 1.73 m² BSA
- Cardiac output: Cardiac index is calculated as cardiac output divided by BSA
- Burn assessment: Percentage of burned surface area is estimated using BSA charts
- Pharmacokinetics: Drug clearance and volume of distribution are often normalized to BSA
Normal BSA Values:
- Average adult male: 1.9 m²
- Average adult female: 1.6 m²
- Neonates: 0.25 m²
- 2-year-old child: 0.5 m²
- 9-year-old child: 1.07 m²
- 10-year-old child: 1.14 m²
- 12-13 year old: 1.33 m²
BSA calculations are essential in medical practice, especially for determining appropriate medication doses for both children and adults, and for comparing physiological measures across individuals of different sizes.