utils logo UTILS
Free online tools to generate, calculate,
convert, format, encode, and play.
 

BSA Calculator

Calculate your Body Surface Area (BSA) using multiple established medical formulas.

Select Units

Enter Your Information

kg
cm

Primary Formula

BSA Formulas

Formula Equation
Du Bois 0.007184 × W0.425 × H0.725
Mosteller √(W × H / 3600)
Haycock 0.024265 × W0.5378 × H0.3964
Gehan-George 0.0235 × W0.51456 × H0.42246
Boyd 0.0003207 × W0.7285 − 0.0188 log(W) × H0.3

W = weight in kg, H = height in cm

How It Works

Body Surface Area (BSA) estimates the total surface area of the human body. It is used extensively in medicine to calculate drug dosages, determine cardiac index, and assess burn injuries.

BSA is more accurate than body weight alone for these purposes because it correlates more closely with metabolic rate. The average adult BSA is approximately 1.7 m².

Common BSA Ranges

  • Newborn: ~0.25 m²
  • Child (10 years): ~1.14 m²
  • Average adult female: ~1.6 m²
  • Average adult male: ~1.9 m²

Medical Applications

  • Drug dosing: Chemotherapy and other medications are often dosed per m² of BSA
  • Cardiac index: Cardiac output divided by BSA normalizes heart function across body sizes
  • Burn assessment: BSA helps estimate the extent of burn injuries
  • Renal function: GFR is often normalized to 1.73 m² BSA

Which Formula Should I Use?

  • Du Bois: Most widely used and referenced in medical literature
  • Mosteller: Simplest formula, commonly used in clinical practice
  • Haycock: Recommended for pediatric patients
  • Gehan-George: Developed from a large dataset; good general accuracy
  • Boyd: One of the earliest formulas; accounts for weight variations
Disclaimer: This calculator is for informational and educational purposes only. It should not replace professional medical advice. Consult a healthcare provider for clinical BSA calculations.

Embed This Util

You can embed this util on your own site as a widget. Adding ?embed=1 to the URL loads a compact version with just the tool itself; no header, menu, or documentation. Paste this snippet into your HTML: 


    

       Copy snippet
      Adjust the height to taste.
    

  




    


  

    
 Related Utils

    

      

         BMI Calculator
         Body Fat
         Ideal Weight
         BMR Calculator
      

    

  


          

          

          

              Feedback
          

          

            

              Help us improve this page by providing feedback,
              and include your name/email if you want us to reach back. Thank you in advance.
            

            

              
              

              
            

          

          
          
          
          

          

            Share with