Calculate body surface area in square metres with the Mosteller and Du Bois formulas — the two standard published equations, shown side by side. Runs entirely in your browser — your numbers never leave this device.
Body surface area is used in clinical dosing contexts. This page is the arithmetic only.
Informational only. This calculator applies a published formula to the numbers you enter — it is not medical advice, a diagnosis, or a substitute for a clinician. Talk to a qualified professional about decisions concerning your health.
| Formula | Equation | Source |
|---|---|---|
| Mosteller | √(H cm × W kg ÷ 3600) | Mosteller, 1987 |
| Du Bois | 0.007184 × H^0.725 × W^0.425 | Du Bois & Du Bois, 1916 |
Body surface area expresses the size of the body as an area in square metres, estimated from height and weight. Two published equations dominate: Mosteller (1987), which takes the square root of height times weight divided by 3,600, and Du Bois and Du Bois (1916), which raises height and weight to fractional powers with the constant 0.007184. The page calculates both, because the pair are the reference forms against which other surface-area equations are compared.
On typical inputs the two formulas agree closely — both return 2.00 m² for the first worked example — and small differences appear at other sizes, as the second example shows (1.73 against 1.72 m²). Presenting both keeps that agreement, and its limits, visible rather than implied.
The formulas and their publication sources are listed in the table. The output is the formulas' arithmetic for information only; clinical uses of surface area are matters for the clinicians applying them.
Mosteller (1987) and Du Bois and Du Bois (1916) are the two published equations in standard use. They were derived decades apart by different methods and agree closely on typical inputs; the page shows both so any difference is visible.
Square metres. Both formulas take height in centimetres and weight in kilograms and return square metres, which is the unit the result is reported in.
Mosteller is the form most often cited in current clinical references because of its simplicity; Du Bois remains the historical reference equation. This page reports both outputs without selecting between clinical practices.
No. The page computes two published formulas for information only. Any clinical application of a surface-area figure belongs with the treating clinician.
No. The calculation runs entirely in the browser and nothing entered is uploaded, stored or tracked.
More in Health & Body Calculators · Browse all tools