Body Surface Area (BSA) Calculator: Mosteller and DuBois
Enter height and weight to calculate your body surface area in square metres with two standard formulas.
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Body surface area (Mosteller)
1.82m²
- DuBois formula
- 1.81 m²
- Difference between formulas
- 0.01 m²
An estimate for general information, not medical advice.
For information only. Never use this to work out a medicine dose.
How to use
- Enter height in cm or feet and inches.
- Enter weight in kg.
- Compare Mosteller and DuBois results.
Good to know
Mosteller (1987): BSA = √(height cm × weight kg ÷ 3600). DuBois and DuBois (1916): BSA = 0.007184 × weight^0.425 × height^0.725. For most adults the two agree within a few hundredths of a square metre.
An average adult has a BSA of about 1.6–1.9 m². BSA is used in medicine to scale some measurements, such as cardiac index and kidney filtration rate.
This page is for learning and general information. Medicine doses must be decided by your doctor or pharmacist, never from an online calculator.
Questions
What is a normal body surface area?
About 1.9 m² for an average adult man and 1.6 m² for an average adult woman, but it varies with size.
Which BSA formula is used most?
Mosteller, because it is simple and accurate enough for most adults. DuBois is the oldest and still common.
Can I use this for chemotherapy or other dosing?
No. Doses are set by your care team using clinical checks. Do not change any medicine based on this page.
Does BSA change with weight loss?
Yes, slightly. Losing 10 kg at 170 cm lowers Mosteller BSA by about 0.13 m².
Is my data stored?
No. Everything is calculated on your device.