Body Surface Area Calculator (BSA)
Body surface area calculator: BSA in m² from height and weight (Mosteller formula), with the Du Bois estimate for comparison.
BSA = √H · W3600
How to use this calculator
- Choose the quantity you want under “Solve for”.
- Type the known values and pick their units: any combination works.
- The result updates as you type. Open “Show the steps” to see the substitution.
BSA is used to dose some medicines and to index measurements such as cardiac output. Average adult BSA is about 1.7–1.9 m².
For general information only; it does not replace advice from a doctor or other health professional.
Formula
BSA = √H · W3600
| Symbol | Quantity | Units |
|---|---|---|
| W | Weight | kg, g, mg, µg, t, lb, oz, st, US ton, ct, Da |
| H | Height | m, km, cm, mm, µm, nm, pm, Å, in, ft, yd, mi, nmi, au, ly |
| BSA | Body surface area | m², km², cm², mm², ha, ft², in², yd², ac, mi² |
Constants used: Mosteller formula · H in cm, W in kg
Worked example
Given: W = 70 kg · H = 175 cm
BSA = √H W3600
Result: BSA = 1.84466 m²
Body surface area for different values of Weight
| W · Weight | BSA · Body surface area |
|---|---|
| 56 kg | 1.6499 m² |
| 63 kg | 1.75 m² |
| 70 kg | 1.8447 m² |
| 77 kg | 1.9347 m² |
| 84 kg | 2.0207 m² |
| 91 kg | 2.1032 m² |
Other values as in the worked example.
Frequently asked questions
70 kg and 175 cm?
BSA ≈ 1.84 m².
Related calculators
- Blood Alcohol Content Calculator (BAC)
- Lean Body Mass Calculator
- Waist-to-Hip Ratio Calculator
- Waist-to-Height Ratio Calculator
- Conception Date Calculator
- Period Calculator (Next Period Date)
- Steps to Miles Calculator
- Blood Sugar Converter (mg/dL ⇄ mmol/L)
Last updated: · Report an error