Body Surface Area Calculator (BSA)
Body surface area in m² using the Mosteller, Du Bois, Haycock and Gehan–George formulas.
Result
How to use
- 1
Enter height in cm.
- 2
Enter weight in kg.
- 3
See your body surface area from four common formulas.
Questions
What is body surface area used for?
Doctors use BSA to work out doses of some medicines, especially chemotherapy, and to adjust measurements such as cardiac index and kidney function. An average adult has a BSA of about 1.6–1.9 m².
Which formula is most common?
The Mosteller formula, √(height in cm × weight in kg ÷ 3600), is the simplest and most widely used. The Du Bois formula (1916) is the oldest, and Haycock is often used for children.
Can I use this to calculate my own medicine dose?
No. This is for information only. Medicine doses must always be decided by your doctor or pharmacist.
About this Body Surface Area tool
Body Surface Area Calculator (BSA) — Body surface area in m² using the Mosteller, Du Bois, Haycock and Gehan–George formulas. It is one of 200 free tools on namasivayam.in, made by software engineer Namasivayam Vadivelan for everyday use in India.
Everything is calculated instantly in your browser: nothing you type or upload is sent to any server, there is no sign-up, and it works on mobile and desktop. Enter height in cm.
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Results are estimates to help you plan. They are not financial, tax or medical advice.