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Body Surface Area Calculator

Get your BSA in m² using three clinical formulas — Du Bois, Mosteller, and Haycock.

Body Surface Area (average)
1.82
Du Bois1.81
Mosteller1.818
Haycock1.826

Why BSA Matters in Medicine

Many drugs are dosed in mg per m² of body surface area — especially chemotherapy agents. BSA also determines cardiac index (cardiac output / BSA) and is used in burn %, IV fluid, and pediatric dosing calculations.

Du Bois: 0.007184 × W^0.425 × H^0.725
Mosteller: √(W × H / 3600)

Frequently Asked Questions

What is BSA used for?

Body Surface Area is used in medicine for drug dosing (especially chemotherapy), calculating cardiac index, burn-injury assessment, and pediatric care.

Normal BSA range for adults?

Around 1.7 m² is average. Men typically 1.9 m², women 1.6 m². BSA below 1.3 m² or above 2.5 m² is unusual.

Which BSA formula is best?

Mosteller is widely used in clinical practice (simple, accurate). Du Bois (1916) is the historic standard. Haycock is preferred for children. Results usually differ by less than 3%.

Is BSA the same as BMI?

No. BMI relates weight to height-squared; BSA estimates total skin-surface area in m². BSA scales better with metabolic rate and drug distribution.

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