Body Surface Area Calculator

BSA Calculator estimates the body surface area based on body weight and height. To calculate BSA, the calculator uses the most well-known formulae. By following a few quick and easy procedures now you can calculate your Body Surface Area. Choose the equation that you want to use on Body Surface Area Calculator and get the results quickly.


Body Surface Area Calculator: People who show interest in calculating their body surface area can use this free BSA Calculator. Body Surface Area is useful in medicine and physiology. You can check the body surface area chart, and steps to find BSA with an example question. Also, get different Body Surface Area Formulas.

What is Body Surface Area?

Body Surface Are or BSA is a measure or calculation of the external surface area of a human body. If you want to determine the metabolic mass, BSA is a better indicator than bodyweight because it is not affected by abnormal adipose tissue.

Body Surface Area Formula

There are various equations to calculate BSA.

The Du Bois equation

BSA = 0.007184 × weight [kg]0.425 × height [cm]0.725

The Mosteller equation

BSA = 0.016667 × weight [kg]0.5 × height [cm]0.5

The Haycock equation

BSA = 0.024265 × weight [kg]0.5378 × height [cm]0.3964

The Gehan & George equation

BSA = 0.0235 × weight [kg]0.51456 × height [cm]0.42246

The Boyd equation

BSA = 0.03330 × weight [kg](0.6157 - 0.0188 × log10 (weight [kg])) × height [cm]0.3

The Takahira equation

BSA = 0.007241 × weight [kg]0.425 × height [cm]0.725

The Schlich equation


 BSA = 0.000975482 × weight [kg]0.46 × height [cm]1.08


 BSA = 0.000579479 × weight [kg]0.38 × height [cm]1.24

Body Surface Area Chart

Values of the average body surface area 


BSA value in m2

Adult man


Adult woman


Child 12 to 13 years


Child of 10 years


Child of 9 years


Child of 2 years


Newly born


Steps to Calculate Body Surface Area Using Weight & Height

The simple step by step process to calculate BSA (Body Surface Area) is given here:

  • Measure the height and weight of a person.
  • Use one Body Surface Area Formula.
  • Substitute the height and weight values in the BSA formula.
  • Perform the required calculations to obtain the answer. 

Solved Example of BSA Calculation using Formula


Calculate the BSA of a person with having bodyweight of 78kg & height of 164cm.


Here body weight and height are given as 78kg and 164cm respectively.

Let us first select the equation to calculate BSA. We will use the Takahira equation for calculation.

BSA = 0.007241 × weight0.425 × height0.725

Now, put the values of height & weight in the above equation,

We get the result as,

BSA = 1.861 m2

Start utilising other calculators for your convenience, and visit Arithmetic Calculators for health information.

FAQs on Total Body Surface Area Calculator

1. Is body surface area the same as BMI?

No, BMI is a measure of a person's body fat mass, whereas the Body Surface Area is used to measure the total surface area of a person's body.

2. What is a normal body surface area?

Generally, 1.7 m2 is considered to be the normal body surface area but actually, it depends on a person's height and weight.

3. Why do infants have a higher body surface area?

Infants have a higher body surface area because of higher body water content in the body of infants and higher metabolic rates.

4. What is a good waist size for a man?

If the waist size is less than 40 inches around then it is considered as a good waist size for a man.