Body Surface Area: BSA Calculator

BSA Calculator

The BSA calculator makes calculating the external surface area of the human body in square meters simple or your body surface area (BSA). Furthermore, BSA is a more accurate measure of metabolism than bodyweight, thus knowing how to calculate it will be highly valuable in medicine and physiology. Therefore, the BSA formula is a tool used by so many doctors when writing prescriptions.

Because BSA is a more accurate predictor of metabolic mass (the body’s requirement for energy) than bodyweight, they frequently employed it in clinical settings. However, body fat is not metabolically active; we can approximate metabolic mass as fat-free mass. 

We use BSA in a variety of therapeutic situations, including calculating cardiac index (a measure of a person’s heart performance in relation to their body size) and chemotherapy dosages (a category of cancer treatment). While a patient’s BSA is frequently used to estimate chemotherapy treatment, there are arguments against using BSA to determine dosages for medications with a limited therapeutic index.

Formula for BSA Calculator

We can calculate body surface area using several formulas. By default, our BSA calculator employs the most prevalent form, the Du Bois formula. In advanced mode, however, there are many BSA formulations to choose from (Shuter and Aslani, Haycock, Mosteller, Boyd, Fujimoto, Takahira, Schlich separately for men and women and Gehan and George). To use any of these calculations, all you need is your weight and height. Let’s look at a couple of them.

Here are some formulas:

Du bois: BSA= 0.007184 X HEIGHT X WEIGHT

Hay cock: BSA = 0.024265 X HEIGHT X WEIGHT

Gehan & George: BSA = 0.51456 X HEIGHT X WEIGHT

Fujimoto: BSA = 0.008883 X HEIGHT X WEIGHT

Mosteller: BSA (m2) = SQRT ((WEIGHT (KG) X HEIGHT (CM)/ 3600)

Takahira: BSA = 0.007241 X HEIGHT X WEIGHT

Where the BSA expressed in square meters, we measured the height in millimeters and we measured the weight in kilos. Don’t worries, our tool make it simple to use alternative units? All the formulas are from Wikipedia’s article on Body Surface Area.

BSA Calculator: What Is The Purpose of Using This Body Surface Area Calculator?

You won’t have to figure out your BSA on your own, which is a good thing. However, using the body surface area calculator will save you time and effort in the long run. If you were in a flat region, you could use this tool to determine your body size. Although the calculator is based on some sophisticated mathematics, it is straightforward to use and takes only a few seconds if you already know your weight and height.

Knowing how to calculate your BSA can provide you with information about your health that other measurements cannot. Your body surface area, for example, can show coronary artery calcium, which is a major medical risk. This distinguishes BSA from BMI, which, while useful for assessing your general health state based on weight, cannot predict this condition.

Our BSA calculator is the most convenient way to figure out your body surface area. To answer the equation, this tool only needs your weight and height. You’ll automatically get a result after plugging in these two numbers.

For example

A man with a weight of 55kg and a height of 175cm

Your body surface area is roughly 1.64 square meters based on this data. However, it’s helpful to understand the average BSA values before calculating your BSA. They’re separated by gender and age.

The average surface area of the body for:

Women: 1.6m2, Men: 1.9m2, Infants: 0.25m2, Children of 2 years: 0.5m2, Children of 10 years: 1.14m2 

BSA Calculator: Other Factors to Consider

If you’re curious about various body dimensions, use our BMI calculator (link above). This is a tool that can help you determine whether your weight is within a healthy range. However, the surface area calculator is another tool you might find handy.

Although BSA shows metabolic rate, it has been criticized. The most crucial application is in determining the dosage of drugs with a small margin of error, such as chemotherapy.


The total surface area of a human body, often known as body surface area, determined with our BSA calculator (BSA). BSA is difficult to measure directly. It showed some of the most common formulas in the calculator.

We know the measured or computed surface area of a human body as body surface area (BSA). Because BSA is less affected by aberrant adipose mass, it is a better indicator of metabolic mass for many clinical applications than body weight. Using BSA in deciding the dosage of drugs having a limited therapeutic index, such as chemotherapy, has been subjected to several significant criticisms.


What role does body surface area play in the human body?

We know the measured or computed surface area of a human body as the body surface area (BSA) in medicine and physiology. Because BSA is less affected by aberrant adipose mass, it is a better indicator of metabolic mass for many clinical applications than body weight.

For chemotherapy, why do we use body surface area?

In order to standardize drug concentrations, dosing based on body surface area (BSA) is commonly employed. However, this is because it is widely known that the use of BSA helps standardize measurements of a variety of physiologic factors involved in drug disposition, such as renal function and energy expenditure.

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