Body Surface Area Calculator

Calculate body surface area with five clinical formulas - used for chemotherapy dosing, cardiac indices and metabolic calculations.

Mosteller (most common)

1.845 m²

Du Bois

1.848 m²

Haycock

1.847 m²

Gehan & George

1.854 m²

Boyd

1.851 m²

Average adult BSA is about 1.9 m\u00B2 for men and 1.6 m\u00B2 for women. Clinical dosing protocols specify which formula to use.

How to Use the Body Surface Area Calculator

  1. Enter height and weight in metric or imperial units.
  2. Review the five formula outputs side by side; Mosteller is the most common default.
  3. Use the result for clinical dosing or physiological index calculations as directed by a professional.

Formulas Used

Mosteller: BSA = √(height(cm) × weight(kg) / 3600)

Du Bois: BSA = 0.007184 × height^0.725 × weight^0.425

Haycock: BSA = 0.024265 × height^0.3964 × weight^0.5378

Frequently Asked Questions

What is a normal BSA value?

Average adult values are about 1.9 m² for men and 1.6 m² for women, but healthy ranges vary widely with height and weight.

Why is BSA used for drug dosing?

Many drugs - especially chemotherapy agents and some anaesthetics - scale better with surface area than raw weight because it reflects metabolic mass more closely.

Which BSA formula should I use?

Mosteller is the most widely used clinically because it is easy to compute mentally. Oncology protocols usually specify which formula to apply - differences between them are small.