Body Surface Area Calculator
Estimate your Body Surface Area (BSA) using various formulas.
Your results will be displayed here.
What is Body Surface Area (BSA)?
Body Surface Area (BSA) is the measured or calculated surface area of a human body. For many clinical purposes, BSA is a better indicator of metabolic mass than body weight because it is less affected by abnormal body fat. The calculation of BSA is a common practice in medicine for calculating the dosage of medications with a narrow therapeutic index, such as chemotherapy drugs.
BSA Formulas
Direct measurement of BSA is difficult, so numerous formulas have been developed to estimate it based on height and weight. This calculator provides results from several of the most popular formulas for comparison.
- Mosteller Formula (1987): This is one of the simplest and most commonly used formulas today due to its ease of calculation.
- Du Bois Formula (1916): The most widely cited formula, it has been shown to be effective for estimating body fat in both obese and non-obese patients.
- Haycock Formula (1978): Developed for use in pediatric patients but also used for adults.
- Gehan & George Formula (1970): Another formula used in clinical settings.
- Boyd Formula (1935): A more complex logarithmic formula.
For more information on the use of BSA in oncology, you can refer to publications from the National Cancer Institute.
Frequently Asked Questions
Why is Body Surface Area (BSA) used in medicine?
BSA is often used in clinical settings because it can be a better indicator of metabolic mass than body weight alone. Since many drug dosages, especially in chemotherapy, relate to metabolic rate, using BSA can lead to more accurate and safer dosing. It helps tailor medical treatments to an individual's body size.
Which BSA formula is the most accurate?
There is no single 'best' formula, as each was validated on different populations. The Du Bois formula is the most widely cited and used historically. However, the Mosteller formula is much simpler to calculate and is often preferred for its ease of use while providing very similar results to the Du Bois formula for most individuals.
Is a higher or lower BSA better?
BSA is a neutral measurement of total body size, much like height or weight. It is neither 'good' nor 'bad' to have a higher or lower BSA. Its primary purpose is to serve as a variable in other medical calculations, not as a direct indicator of health itself.