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Calculate Body Surface Area (BSA) based on height and weight using multiple medical formulas. Ideal for medication dosage estimation and physiological research.
Enter height and weight to see BSA results

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When you need to accurately calculate chemotherapy dosages, assess burn areas, or conduct physiological research, Body Surface Area (BSA) is a more scientific parameter than body weight alone. By inputting height (cm) and weight (kg), this tool applies various classic medical formulas—including Mosteller, DuBois, and Haycock—to automatically calculate BSA in square meters (m²). BSA is a key indicator of the total surface area of the human body, commonly used for individualized adjustments of clinical medication dosages (such as chemotherapy drugs).
Q: What is the difference between the BSA calculated by the Mosteller formula and the DuBois formula?
A: For the same height and weight, different formulas usually yield slight variations (about ±3% to 5%). For example, for an adult who is 175 cm tall and weighs 70 kg, the Mosteller formula gives a result of approximately 1.87 m², while the DuBois formula yields about 1.85 m². The specific difference depends on the derivation population and mathematical model of the formula. In clinical use, it is recommended to follow specific guidelines or research protocols to standardize the formula used.
Q: What are the input units for the BSA calculator?
A: The unit for height is centimeters (cm), and the unit for weight is kilograms (kg).
The calculation results of this tool are for reference only and cannot replace professional medical diagnosis and prescription. Input values must be valid numbers. Extreme height and weight values (such as for infants or extreme obesity) may exceed the original validation range of certain formulas, so results should be interpreted with caution. The tool does not store any input data; all calculations are performed locally in your browser.
In clinical practice, choosing a BSA calculation formula requires considering the target population and specific application scenarios. The Mosteller formula is widely adopted in most clinical settings because it is easy to calculate and applicable to all age groups. The DuBois & DuBois formula has the longest history and is often seen in early research. The Haycock formula is better suited for children and infants. For instance, when calculating adult chemotherapy dosages, you can first use the Mosteller formula to obtain a baseline BSA (e.g., height 160 cm, weight 60 kg → BSA ≈ 1.65 m²), and then adjust the dosage per square meter according to the specific drug label based on the body surface area. Please note that medical guidelines in different countries or hospitals may specify the use of a particular formula; always refer to your local guidelines.