Body surface area calculator
Clinicians use body surface area for chemotherapy doses and to index some heart and kidney measures.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Enter weight and height.
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
Mosteller = √(height cm × weight kg ÷ 3600). Du Bois = 0.007184 × W^0.425 × H^0.725. Haycock = 0.024265 × W^0.5378 × H^0.3964. Gehan and George = 0.0235 × W^0.51456 × H^0.42246.
Example
Inputs: Weight = 70 kg, Height = 175 cm. Result: Mosteller: 1.84 m²; Du Bois: 1.85 m²; Haycock: 1.85 m².
Limits and caveats
- For information only; drug doses must be set by a doctor and pharmacist.
- The formulas differ slightly, and the gap widens at very high weights.
Questions about this tool
What is an average body surface area?
Roughly 1.9 m² for an adult man and 1.6 m² for an adult woman.
Which formula do hospitals use?
Mosteller is the most common because it is simple; Du Bois is the oldest and still in use.
Why not dose by weight alone?
For some drugs, surface area tracks metabolic rate and kidney clearance more closely than weight.