Body Surface Area Calculator
BSA with the Mosteller, DuBois, Haycock, Gehan–George and Boyd formulas.
Enter your values to see the result.
Mosteller is the most widely used formula for drug dosing; DuBois is traditional in physiology, and Haycock is validated in infants and children. For education and clinical decision support only. Results do not replace professional judgment, local protocols or the product information, so always verify doses and values before acting on them.
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- Drug Dose Calculator — Calculate a mg/m² dose.
- Adjusted Body Weight Calculator — Get ideal and adjusted weight.
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Clear instructions
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How to use the Body Surface Area Calculator
BSA with the Mosteller, DuBois, Haycock, Gehan–George and Boyd formulas.
- 1 Choose metric or imperial units.
- 2 Enter height and weight.
- 3 Read the BSA from each formula; Mosteller is the usual choice for dosing.
Example and practical tips
A person 170 cm tall weighing 70 kg has a body surface area of 1.82 m² by Mosteller.
Further reading
Frequently asked questions
Which BSA formula should I use?
Mosteller is simple and widely used for chemotherapy dosing. Haycock is validated in infants and children.
Why is BSA used for dosing?
Some drugs, especially cytotoxics, are cleared in proportion to body size, which BSA reflects better than weight alone.
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