The body surface area formulae have been applied in medical situations for decades and were originated by Drs. Du Bois & Du Bois. As a crucial index of human physiological functions, BSA has always been used to get the appropriate measurement of various organs functionality before appropriate treatment plans can be commenced. For example, body surface area is preferred to the Ideal Body Weight (IBW) for kids when doctors need to standardize physiological functions of oxygen consumption, cardiac index, metabolic rate, and glomerular filtration rate.

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In many cases, medical experts prefer to use body surface area because it presents a better correlation to many treatments. Notably, unlike the ideal body weight calculations that have lately been associated with controversies, getting the body surface area is relatively easy. In this post, we compare the different body surface area (BSA) calculator formulae to establish their effectiveness and point at the most popular.

A comparative outlook review of different BSA formulae

The direct coating, triangulation, and surface integration, body surface area techniques by Boyd in 1935 were initially considered to be more accurate. However, the Boyd formula is very difficult, takes a lot of time, and many doctors have considered it impracticable especially in the field.

Boyd formula:

BSA [m2] = Weight [g](0.7285 - (0.0188 x LOG(Weight [g])) × Height [cm]0.3 × 0.0003207

Because of these difficulties in application, medical and academic practitioners prefer other alternatives that are simpler than the Boyd formula which include The Du Bois and Du Bois body surface area method of 1916. This formula uses weight and height to estimate the body surface area:

Dubois and Dubois formula of 1916:

BSA [m2] = Height[m]0.725 x weight[kg]0.425 x 0.20247

The equation, is derived from the mathematical application of a few patients and a kid. As a result, it has become less applicable in different populations.

Other formulae that have been considered better alternatives include:

The Haycock and Schwarz formula of 1978:

(BSA [m2] = Weight [kg]0.5378 × Height [cm]0.3964 × 0.024265)

The Mosteller formula of 1987:

BSA [m2] = √(Height [cm] × Weight [kg] / 3600)

The Takahira formula of 1925:

(BSA [m2] = Weight [kg]0.425 × height [cm]0.725 × 0.007241

The Gehan and George formula of 1979:

(BSA [m2] = Weight [kg]0.51456 × Height [cm]0.42246 × 0.02350)

It is important to note that successive BSA formulae were mainly evidence based but specifically targeted at making calculations easier and inclusive to make results more acceptable. For example, the complex outlook of the Dubois and Dubois formula made many medical practitioners and academicians make huge mistakes that compromised its application. Mosteller relooked at the Dubois and Dubois among other formulae and tried to address their shortcomings using his new equation of 1987.

Even the latter body surface area (BSA) formulae like Fujimoto as well as Schlich were also targeted at making it easier for medics and academicians still fell short of coming with a fully acceptable equation. Schlich went further to add gender in his formula so that his equation has two formulae (one for males and another for females).

Fujimoto formula:

BSA [m2] = Weight [kg]0.444 x Height [cm]0.663 x 0.008883

Schlich formula

BSA [m2] (male) = Weight [kg]0.38 x Height [cm]1.24 x 0.000579479

BSA [m2] (female) = Weight [kg]0.46 x Height [cm]1.08 x 0.000975482

Shuter and Aslani formula:

0.00949 x Weight [kg]0.441 x Height [cm]0.6555

Wang and Hihara formula:

√(Weight [kg] x Height [cm]) / 3537

Today there lacks a standard instrument and formula to get direct body surface area in the medical facilities, academic applications and emergencies. However, repeated 3-dimensional scans have been applied at times to get correct results though medical practitioners indicate that it is cumbersome. Besides, it is lengthy, costly and application on a daily basis in clinics is not practical.

The final verdict

It is prudent to note that the choice of a specific formula for establishing BSA should be carefully selected depending on the conditions of applications. In most of the formulae, the body surface area prediction is overestimated with a wide range of 3% to 15% depending on the application. This makes it very difficult to tell with precision the best method. From the review, the Gehan-George equation comes out stronger because it relies on direct measurement, the error margin is also low, and can be used both in adults and children. It is, therefore, the most preferred and favourite to most medical and academic practitioners.

Note: 1 kilogram (kg) = 2.2 pounds (lb), 1 meter = 3.28084 feet


1. Mosteller RD. Simplified Calculation of Body Surface Area. N Engl J Med 1987 Oct 22;317(17):1098. (letter)

2. DuBois D, DuBois EF. A formula to estimate the approximate surface area if height and weight be known. Arch Int Med 1916 17:863-71.

3. Haycock GB, Schwartz GJ, Wisotsky DH. Geometric method for measuring body surface area: A height weight formula validated in infants, children and adults. The Journal of Pediatrics 1978 (93):1:62-66.

4. Gehan EA, George SL. Estimation of human body surface area from height and weight. Cancer Chemother Rep 1970 54:225-35.

5. Gehan EA, George SL. Estimation of human body surface area from height and weight. Cancer Chemother Rep 1970;54:225-35.

6. Haycock GB, Schwartz GJ, Wisotsky DH. Geometric method for measuring body surface area: A height-weight formula validated in infants, children and adults. J Pediatr 1978;93:62-6.

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8. Verbraecken J, Van de Heyning P, De Backer W, Van Gaal L. Body surface area in normal-weight, overweight, and obese adults. A comparison study. Metabolism. 2006 Apr;55(4):515-24.

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10. Livingston E. H. & Lee S. Body surface area prediction in normal-weight and obese patients. Am. J. Physiol.-Endocrinol. Metab. 281, E586–E591 (2001).