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Body measurements · Clinical reference

Body Surface Area Calculator

BSA for medical dosing and clinical reference.

Your details

Height
Weight
Average BSA
1.82m²
By formula
Mosteller (1987)
Most widely used in clinical practice.
1.82 m²
Du Bois (1916)
The historical reference formula.
1.81 m²
Haycock (1978)
Suited to children and lower body weights.
1.83 m²
Boyd (1935)
Older, less commonly used.
1.83 m²

What is BSA?

Body Surface Area estimates the total surface area of your body — useful clinically because many physiological processes (cardiac output, drug dosing, dialysis) scale with surface area rather than weight.

The four most-cited formulas

Mosteller (1987) is the modern clinical default. Du Bois (1916) is the historical reference. Haycock (1978) is preferred for children. Boyd (1935) is less commonly used.

How clinicians use BSA

Chemotherapy and narrow-therapeutic-index drugs are dosed per m² BSA. Cardiology uses indexed cardiac output. Burn assessment and dialysis are BSA-calibrated.

Limitations & caveats

  • BSA is an estimate — actual surface cannot be measured non-invasively.
  • Formulas drift in extreme body types.
  • Not a wellness target — a clinical reference.
  • Mosteller is the modern default.
  • Paediatric dosing typically uses Haycock.
FAQ

Frequently asked questions

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Medical Evidence

How we ground the Body Surface Area

Grade A · Clinical guidelines & meta-analysesLast reviewed Nov 1, 2025
Named clinical guidelines
  • Mosteller RD (1987) — clinical default
  • Du Bois D (1916) — historical reference
  • Haycock GB (1978) — paediatric preferred
References

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