Fitness & Health

Body Surface Area Calculator (Mosteller, DuBois, Haycock)

Calculate body surface area with three validated formulas: Mosteller for standard adults, DuBois as the classic, and Haycock for pediatrics. Clinicians use BSA for chemotherapy and fluid dosing.

How to use
  1. Enter height and weight.
  2. Pick the formula: Mosteller, DuBois, or Haycock.
  3. Switch units if needed.
Estimates for general wellness, not medical advice. Check with a doctor or dietitian before acting on health figures.
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Common questions

Which BSA formula should I use?

Mosteller is the common choice for adults because it is simple and accurate, while Haycock is preferred for children.

Why is body surface area used for dosing?

BSA tracks metabolic rate better than weight alone, so chemotherapy and fluid doses are often scaled to it.

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