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Body Surface Area (BSA) Calculator

Calculate body surface area (BSA, m²) from height and weight. A free tool supporting the international-standard Du Bois formula and the Fujimoto formula for Japanese people.

Input

This tool gives an estimate based on standard formulas. Always consult a doctor for any medical decision such as diagnosis or treatment.

Formula
cm
kg

Result

Body surface area (BSA)

1.69m²

Calculated with the Du Bois formula

Formula

Du Bois formula

Height

170 cm

Weight

60 kg

How it works

  • Body surface area (BSA: Body Surface Area) is estimated from height and weight and is used for setting drug dosages, comparing metabolic rates, and similar purposes.
  • Du Bois formula (the standard formula used widely worldwide): BSA(m²) = 0.007184 × height(cm)^0.725 × weight(kg)^0.425.
  • Fujimoto formula (a formula developed for Japanese people): BSA(m²) = 0.008883 × height(cm)^0.663 × weight(kg)^0.444. For Japanese body types, the Fujimoto formula is considered closer to measured values in some cases.
  • Even for the same height and weight, the result differs slightly depending on which formula is used. Choose the formula according to your purpose.
  • This tool calculates for heights of 50–250 cm and weights of 5–300 kg. For extreme body types or children, the estimation formulas may fall outside their assumptions and produce larger errors.
  • This tool is a general estimate based on formulas and is not a diagnosis or medical service. Always consult a doctor for health-related decisions.