Estimate body surface area (BSA) in m² from height and weight using the Mosteller, Du Bois and Du Bois, and Haycock formulas. Metric and imperial units, converted values and every formula shown. Not for calculating any medical dose.
Body Surface Area Calculator estimates body surface area in square metres from height and weight. It uses three published formulas — Mosteller, Du Bois and Du Bois, and Haycock — and shows each result side by side with the formula, the values used and the spread between them. Height can be entered in centimetres, metres, feet and inches or inches, and weight in kilograms, pounds or stones and pounds.
The formulas were fitted to different groups of people, so their results differ slightly; all of them are mathematical estimates. This tool is for general education only. It must not be used to determine any medicine, chemotherapy, anaesthesia or other clinical dose, and it does not calculate dosages, cardiac index, eGFR or any treatment value. Clinical calculations must be done and checked by qualified healthcare professionals.
Body surface area (BSA) is an estimate of the total outer surface of the body in square metres, calculated from height and weight.
Each formula was developed from measurements of different groups of people, so they produce slightly different estimates, especially at very small or very large body sizes.
No. This tool must not be used to determine any medicine, chemotherapy, anaesthesia or other clinical dose. Those calculations must be made and checked by qualified healthcare professionals.
BSA = √(height in cm × weight in kg ÷ 3600). It is simple and widely referenced.
No. It only shows BSA estimates and does not calculate cardiac index, eGFR, dosages or any treatment values.
Heights from 30 to 250 cm and weights from 1 to 350 kg. Values outside this range are rejected as implausible.
No. Everything is calculated in your browser. Your measurements, dates and results are not sent anywhere or saved in browser storage, and Reset clears them from the page.
