Body Surface Area Calculator
Enter your height and weight to calculate body surface area in square meters with the Mosteller formula, shown next to the Du Bois formula for comparison.
Last updated November 2, 2026
Result
Body surface area: 1.79 m² (Mosteller)
| Measure | Value |
|---|---|
| Mosteller | 1.79 m² |
| Du Bois (for comparison) | 1.79 m² |
BSA is used in some clinical dosing, but doses must come from a prescriber, never from this tool. General estimate only, not medical advice. Talk to a qualified health professional about your own situation.
Show the work
Formula: Mosteller: BSA (m²) = √(height (cm) × weight (kg) ÷ 3600).
- You entered 5 ft 7 in, 150 lb, which is 170.2 cm and 68 kg.
- 170.2 × 68 = 11,578.9, ÷ 3600 = 3.2163.
- Square root = 1.79 m².
- For comparison, Du Bois: 0.007184 × 68^0.425 × 170.2^0.725 = 1.79 m².
Result: Body surface area: 1.79 m² (Mosteller)
How body surface area is calculated
Mosteller: BSA (m²) = √(height (cm) × weight (kg) ÷ 3600)
The Mosteller formula (1987) is the square root of height in centimeters times weight in kilograms, divided by 3,600. For 170.2 cm and 68.0 kg: √(170.18 × 68.04 ÷ 3600) = 1.79 m². Pounds and inches are converted to kilograms and centimeters first.
The Du Bois formula (1916), 0.007184 × weight^0.425 × height^0.725, is another common method and gives a similar answer for most adults, shown here for comparison. Results are estimates and not suitable for any treatment decision.
See how we calculate for the formulas, sources and review schedule behind every calculator.
This is an estimate, not medical advice
Body surface area is used in some medical calculations, but medicine doses must always come from a prescriber, never from this calculator. This page has not been reviewed by a medical professional and gives a general estimate only.
Sources
Official and primary sources for the statements on this page. Their authors have not reviewed or endorsed this page.
- Verbraecken J, Van de Heyning P, De Backer W, Van Gaal L. Body surface area in normal-weight, overweight, and obese adults. A comparison study. Metabolism 2006;55(4):515-524. Its abstract writes the Mosteller formula as [weight (kg) × height (cm) ÷ 3600] to the power 1/2, the form used here, and calls the Du Bois equation the most widely used one
- Mosteller RD. Simplified calculation of body-surface area. N Engl J Med 1987;317(17):1098. Original publication of the Mosteller formula. The PubMed record is a letter with no abstract and the letter itself would not open, so the formula text is confirmed through the Verbraecken abstract above
- Flint B, Das JM, Hall CA. Body Surface Area. In: StatPearls (NCBI Bookshelf NBK559005), last updated February 6, 2025. Gives the Du Bois and Du Bois formula as 0.007184 × height (cm)^0.725 × weight (kg)^0.425, the coefficients and exponents used here
- Du Bois D, Du Bois EF. A formula to estimate the approximate surface area if height and weight be known. Arch Intern Med 1916;17:863-871 (reprinted in Nutrition 1989;5(5):303-311). Original publication of the Du Bois formula. The scanned original has no readable text, so the coefficients are confirmed through the StatPearls chapter above, not the 1916 paper
The StatPearls chapter prints the Mosteller square root over the height alone, which differs from the Verbraecken abstract and from this page. We followed the abstract. The two formulas give slightly different answers, and neither is a clinical dosing tool on its own.
How to use the Body Surface Area Calculator
- Choose US or metric units.
- Enter your height and weight.
- Read the body surface area, then use Copy, Print or Share.
Worked example
A person who is 5 ft 7 in (170.2 cm) and 150 lb (68.0 kg): BSA = √(170.18 × 68.04 ÷ 3600) = √3.216 = 1.79 m². Du Bois also gives 1.79 m².
| Height | Weight | BSA |
|---|---|---|
| 160 cm | 55 kg | 1.56 m² |
| 170 cm | 70 kg | 1.82 m² |
| 180 cm | 85 kg | 2.06 m² |
Frequently asked questions
What is body surface area used for?
Some clinical measures, such as certain dosing or heart output calculations, are scaled to body surface area.
What is the Mosteller formula?
BSA = square root of (height in cm × weight in kg ÷ 3600).
Why do Mosteller and Du Bois give different answers?
They are different fitted equations. For most adults the two differ by only a few hundredths of a square meter.
Can I use this to work out a medicine dose?
No. Doses must come from your prescriber or pharmacist.
Are my numbers stored or sent anywhere?
No. The calculation runs in your browser and nothing you enter is saved or uploaded.