BSA Calculator

Use this BSA calculator to quickly estimate your body surface area using your height and weight. It works for both metric and US units.

Note: This calculator provides an estimate of your body surface area (BSA) based on the Mosteller formula. It is commonly used in medical contexts for drug dosage and other clinical purposes. For the most accurate results, please consult with a healthcare provider or use clinical measurements.

📐 What Is Body Surface Area (BSA)?

Body Surface Area, or BSA, is a measurement of the total surface area of the human body. While it may sound complex, it’s commonly used in medical settings to calculate medication dosages, chemotherapy plans, or fluid needs. Unlike BMI, which is focused on weight relative to height, BSA combines both factors in a way that reflects overall body size more accurately for clinical use.

⚙️ How the BSA Calculator Works

Medical professionals widely accept the Mosteller formula because of its simplicity and accuracy, and this tool uses it to estimate BSA. The formula is:

BSA = √((height in cm × weight in kg) ÷ 3600)

The calculator automatically converts height in inches and weight in pounds before applying the formula for US users. As a result, you get consistent results no matter which unit system you prefer.

💡 Why Use a BSA Calculator?

In many cases, BSA provides a better estimate of how much medication your body can handle than weight alone. For example, chemotherapy drugs are often dosed based on BSA rather than just body mass. Additionally, certain nutritional needs, fluid requirements, and metabolic rates are also calculated using this number. Therefore, using a BSA calculator can improve the accuracy of these assessments.

📏 Metric and US Units Supported

Whether you’re using metric or imperial measurements, this calculator has you covered. Simply select your unit system and enter your height and weight. The conversion happens instantly, so you’ll get accurate results every time without needing to do math on your own.

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