Body Surface Area Calculator
Calculate your body surface area (BSA) in square metres from your weight and height, using both the Du Bois and Mosteller formulas.
Your measurements
How to use this calculator
1. Choose your unit system
Switch between metric (kg / cm) and imperial (lb / ft·in) at the top. Your entries carry over so you don't have to convert manually.
2. Enter weight and height
Type your current weight and standing height. Both formulas use only these two measurements.
3. Compare the two results
The headline shows the Du Bois value; the cards repeat it next to the Mosteller value so you can see how close the two methods are for you.
Which formula should I use?
Mosteller is popular in clinical settings because it is simple to compute and validate by hand. Du Bois is the historical reference. Check which your provider uses if the exact figure matters.
About body surface area
What is body surface area used for?
BSA is the total surface area of the body in square metres. In medicine it is used to scale doses of many drugs, including chemotherapy, and to estimate physiological values like cardiac index and kidney function more fairly than body weight alone.
Why do Du Bois and Mosteller give different numbers?
They are separate equations fitted to different data. The Du Bois formula is the older standard; the Mosteller formula is a simpler square-root version. For most adults the two results are within a couple of percent of each other.
Not medical advice
This calculator is for general information and education only. Never use it to set or adjust a medication dose — drug dosing must be done by a qualified healthcare professional.