Body Surface Area Calculator

Calculates BSA using the Mosteller formula: BSA = √(weight(kg) × height(cm) / 3600). BSA is used in medicine to dose che...

Guides & Reference

How It Works

Calculates BSA using the Mosteller formula: BSA = √(weight(kg) × height(cm) / 3600). BSA is used in medicine to dose chemotherapy, calculate cardiac output, and determine burn severity.

Quick Reference

70kg, 175cm

Mosteller formula

~1.87 m²

60kg, 165cm

Mosteller formula

~1.67 m²

Average adult BSA

Reference value

1.73 m²

Tips & Shortcuts

Average adult BSA is approximately 1.7-1.9 m².

BSA is more accurate than weight alone for drug dosing in oncology.

Burns covering >20% BSA are critical; >40% are life-threatening.

Common Mistakes

Using BSA for all drug dosing

Many drugs use fixed doses or weight-based dosing. BSA dosing is specific to certain medications (mainly chemotherapy).

Confusing BSA with BMI

BSA is the skin surface area in m². BMI is a weight-to-height ratio. Completely different measures.

Frequently Asked Questions

BSA is used to calculate chemotherapy doses, cardiac index, renal function, and burn area estimates. Most chemo drugs are dosed in mg/m² to normalize for body size.

The Mosteller formula (√(height×weight/3600)) is most widely used. DuBois is the historical standard. Haycock is preferred for pediatric patients.

Average BSA is approximately 1.7–1.9 m². Men average about 1.9 m² and women about 1.6 m². Most drug reference doses assume a standard person of 1.73 m².

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