Body Surface Area (BSA) Calculator
Calculate total body surface area using the Mosteller and DuBois formulas.
Mosteller (Standard)
DuBois & DuBois
Haycock
Gehan & George
Estimated Body Surface Area
0.00 m²
What is Body Surface Area (BSA)?
Body Surface Area (BSA) is the measured or calculated surface of a human body. In clinical medicine, BSA is often considered a more accurate indicator of metabolic mass than body weight alone because it is less affected by abnormal adipose tissue (body fat).
Why is BSA Calculation Important?
Calculating BSA is critical in several medical fields for the following reasons:
- Chemotherapy Dosage: Most cytotoxic drugs are dosed based on m² to minimize toxicity while ensuring efficacy.
- Pharmacology: Determining the correct dosage for narrow therapeutic index drugs.
- Kidney Function: Glomerular Filtration Rate (GFR) is typically normalized to a standard BSA of 1.73 m².
- Cardiac Index: Relates cardiac output to the size of the individual.
Common BSA Formulas Used
Our calculator supports the most clinically validated formulas:
- Mosteller Formula: The simplest and most widely used. Calculated as the square root of (height in cm × weight in kg) / 3600.
- DuBois Formula: One of the oldest standards, used frequently in metabolic research.
- Haycock Formula: Often preferred for pediatric patients (infants and children).
Example BSA Calculation
If an adult male stands 180 cm tall and weighs 80 kg, using the Mosteller Formula:
Step 1: 180 × 80 = 14,400
Step 2: 14,400 / 3,600 = 4
Step 3: Square root of 4 = 2.00 m²
Standard Values
While BSA varies significantly based on age and build, the average "standard" BSA for adults is generally considered:
- Men: ~1.9 m²
- Women: ~1.6 m²
- Newborns: ~0.25 m²
- Child (9 years): ~1.07 m²