Enter your height and weight to find your body surface area in m² with the Mosteller, Du Bois, Haycock and Gehan–George formulas.
Last updated: November 8, 2026
Mosteller and other formulas
Body surface area (BSA) estimates the total area of your skin in square meters (m²). Doctors use it to size the doses of chemotherapy and some other drugs, and to index cardiac output and kidney function to body size. With height (H, cm) and weight (W, kg): • Mosteller: √(H × W / 3600) • Du Bois: 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 Example: for 175 cm (5 ft 9 in) and 70 kg (154 lb), Mosteller gives √(175 × 70 / 3600) = √3.40 ≈ 1.84 m². The average for adults is about 1.7–1.9 m². This tool is for information only. Drug doses must always be worked out by a doctor or pharmacist.
Common questions about body surface area
Medical calculations such as chemotherapy and other drug doses, the cardiac index, adjusting kidney function (GFR) and assessing burns.
Other tools you may find useful
Your height without shoes.
Your current weight.