Enter height and weight
Use recent measurements. Small input differences can change BSA enough to matter in formula-based work, especially for children or people outside typical adult size ranges.
Calculadora BSA
Calculadora de Área de Superfície Corporal
Calculadora gratuita de área de superfície corporal com fórmulas Mosteller, Du Bois, Haycock e Gehan.
Health-adjacent note: BSA is often used in clinical formulas and dosing references, but this page is only an educational calculator. Do not use it to choose medication doses, chemotherapy doses, burn-care decisions, or any medical treatment without a qualified clinician.
Calculadora de Área de Superfície Corporal
Enter height and weight, choose the formula requested by your reference or protocol, and get an estimated BSA in square meters. If you are not following a specific protocol, Mosteller is a common default because the equation is easy to verify.
Calculadora de Área de Superfície Corporal
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Selected result
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The BSA from the formula you selected.
Formula used
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Different references may require a specific formula.
Formula comparison
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Lowest to highest estimate across the formulas on this page.
Metric or imperial
Enter cm/kg or ft/in/lb without manual conversion.
Four formulas
Compare Mosteller, Du Bois, Haycock, and Gehan estimates.
Formula range
See how much the common equations differ for the same body size.
Private
All calculations run in your browser.
How to Use the BSA Calculator
The tool is intentionally simple: height, weight, formula, and result. Accuracy starts with current measurements and the formula your use case actually requires.
Choose a formula
Mosteller is widely used because it is easy to calculate. Du Bois, Haycock, and Gehan may appear in specific clinical references, older papers, or pediatric contexts.
Compare the range
If formulas differ meaningfully, follow the method required by your clinician, protocol, calculator reference, or study instead of mixing equations.
Record the context
When you save a BSA number, keep the formula, units, date, height, and weight with it so the result can be checked later.
BSA Formulas Compared
Body surface area formulas estimate the external area of the body from height and weight. They are approximations, not direct measurements, and the best formula is often the one specified by the reference you are using.
| Formula | Equation | Best used when |
|---|---|---|
| Mosteller | BSA = sqrt((height cm x weight kg) / 3600) |
You need a common, easy-to-check BSA estimate for general reference. |
| Du Bois | BSA = 0.007184 x height^0.725 x weight^0.425 |
A reference, protocol, or historical comparison specifically asks for the Du Bois equation. |
| Haycock | BSA = 0.024265 x height^0.3964 x weight^0.5378 |
A pediatric or body-size reference uses Haycock and you need to match that method. |
| Gehan and George | BSA = 0.0235 x height^0.42246 x weight^0.51456 |
You want another historical comparison formula for sensitivity checking. |
How to Interpret BSA
For many adults, BSA commonly falls around 1.5 to 2.2 m², but body size, age, sex, growth stage, and fluid status can shift the result.
- BSA is not the same as BMI. BMI screens weight relative to height; BSA estimates external body area.
- A higher BSA usually reflects a larger body size, not automatically better or worse health.
- Formula choice matters most when a protocol requires one equation or when the person is very small, very tall, or outside typical adult ranges.
- BSA does not describe body composition. Two people can have similar BSA but very different fat mass, lean mass, waist size, or fitness goals.
- For medication, chemotherapy, burn care, kidney function indexing, or clinical decisions, use professional guidance.
Practical use: Use this result as a transparent reference number, then pair it with BMI, body-fat, waist, and clinical context when appropriate.
BSA Calculation Examples
These examples show how BSA reads as a body-size estimate rather than a fitness score or diagnosis.
Average adult example
175 cm and 70 kg
Mosteller BSA is about 1.84 m².
Smaller body size
155 cm and 50 kg
The estimate is lower because both height and weight are lower.
Larger body size
188 cm and 95 kg
The result is higher, but it does not by itself diagnose health status.
Limitations and Safety Notes
BSA is useful, but it is not a complete medical assessment and should not be treated as a stand-alone instruction.
Not a dosing instruction
Medication and chemotherapy dosing require professional protocols, rounding rules, caps, lab values, organ function checks, diagnosis, and clinical judgment.
Formula differences are expected
Mosteller, Du Bois, Haycock, and Gehan can return slightly different estimates for the same height and weight.
Special populations need care
Infants, children, pregnancy, edema, amputation, severe obesity, or acute illness may need specialized assessment.
Body composition is missing
BSA does not show fat distribution, lean mass, or waist risk. Use related body-composition tools when those questions matter.
Related Body and Health Calculators
Use these tools when BSA is only one part of the body-size picture.
Body Surface Area Calculator FAQ
Body surface area, or BSA, is an estimate of the external surface area of the body. It is usually calculated from height and weight and reported in square meters.
A common method is the Mosteller formula: BSA equals the square root of height in centimeters times weight in kilograms divided by 3600. Other formulas include Du Bois, Haycock, and Gehan.
Use the formula required by your reference, clinician, or protocol. If no formula is specified, Mosteller is commonly used because it is simple and easy to verify.
Many adults are roughly between 1.5 and 2.2 m², but there is no single normal value that applies to every person. Body size and the formula used both matter.
No. BMI is weight divided by height squared and is used for weight-status screening. BSA estimates body surface area and is often used in clinical formulas.
Do not use this page alone for medication dosing. Dosing decisions can depend on diagnosis, labs, organ function, drug-specific rules, and clinician judgment.