How to use this calculator
- Enter or choose units.
- The bSA (Mosteller) updates as you type. Use Copy result or Share to keep it.
Method
Mosteller: √(H × W ÷ 3600); DuBois: 0.007184 × W^0.425 × H^0.725; Haycock: 0.024265 × W^0.5378 × H^0.3964; Gehan–George: 0.0235 × W^0.51456 × H^0.42246
- H
- height in cm (1 in = 2.54 cm)
- W
- weight in kg (1 lb = 0.45359237 kg)
Worked example
- Mosteller: √(180 × 80 ÷ 3600) = √4 = 2.00 m².
- DuBois: 0.007184 × 80^0.425 × 180^0.725 = 0.007184 × 6.43 × 43.2 ≈ 2.00 m².
A person 180 cm tall weighing 80 kg has a body surface area of about 2.0 m² by both Mosteller and DuBois.
What the result means
Typical adult values are roughly 1.6–2.0 m². BSA is used to index measurements such as cardiac output (cardiac index) and kidney function, and in some dosing protocols, where the prescriber chooses the formula.
Assumptions and limits
- Height and weight are measured, not estimated.
- Formulas were derived largely in adults (Haycock includes infants and children).
- Formulas diverge at extremes of body size, particularly severe obesity and very small children.
- Not a dosing tool: medicine doses must come from the prescriber, the product label or local protocol.
Questions
Which formula is best?
Mosteller is simple and widely used; DuBois is the oldest and still common in physiology. For most adults the difference is a few hundredths of a square metre. Follow the formula your protocol specifies.
Why is GFR reported per 1.73 m²?
1.73 m² was the average adult BSA when the convention was set, so indexing to it lets kidney function be compared between people of different sizes.
Please note: This is a general screening estimate for adults, not medical advice or a diagnosis. Talk to a qualified health professional about your health.