Back to Health & Fitness

Body Surface Area by Du Bois Formula

Estimate body surface area (BSA) using the Du Bois & Du Bois equation for medication dosing and hemodynamic indexing.

Body Surface Area by Du Bois Formula

Estimate BSA for dosing and hemodynamic normalization.

Input height and weight

Formula details

Du Bois BSA (m²) = 0.007184 × height(cm)0.725 × weight(kg)0.425

The exponents approximate the nonlinear relationship between body size and surface area. BSA is used to index cardiac output (cardiac index), renal function (GFR), and medication dosing.

Steps

  • Enter body height in centimeters.
  • Enter body weight in kilograms.
  • Review the calculated body surface area (BSA) using the Du Bois formula.
  • Use the interpretation to guide drug dosing, chemotherapy planning, or hemodynamic assessments.

Additional calculations

Enter height and weight to view derived metrics.

Guide: interpreting BSA values

Body surface area is most often used to scale doses and normalize physiologic measurements. Average adult BSA is around 1.7 m², but there is wide normal variation by sex, height, and body composition.

BSA (m²)Typical descriptionNotes
< 1.4Small body sizeCommon in smaller adults; double-check dosing caps.
1.4–2.2Typical adultMost reference tables assume BSA in this range.
> 2.2Large/tall body sizeConsider maximum dose limits, especially for chemotherapy.

Always pair BSA-based decisions with clinical judgement, renal/hepatic function, and institutional guidelines rather than relying on BSA alone.

Related calculators

Cardiac Output (Q) Calculator

Calculate cardiac output for hemodynamic assessments.

Caloric Needs Calculator

Estimate energy expenditure based on weight and activity.

Summary

This tool estimates body surface area (BSA) using the Du Bois & Du Bois formula.

Outputs include BSA, qualitative interpretation, recommendations, an action plan, and derived metrics.

Use BSA for medication dosing, fluid calculations, and normalizing physiologic measures such as cardiac output.

FAQs

What is the Du Bois formula?

The Du Bois & Du Bois formula (1916) estimates body surface area (BSA) using BSA = 0.007184 × height(cm)^0.725 × weight(kg)^0.425. Despite its age it remains widely used in clinical dosing.

Why is BSA important?

BSA is used to normalize physiological measurements (e.g., cardiac index) and to calculate safe doses for medications such as chemotherapy, anesthetics, and some antibiotics.

What is a typical adult BSA?

Average adult BSA is ~1.7 m². Values below 1.4 m² generally represent smaller individuals, whereas BSA above 2.2 m² is common in larger or very tall people.

Is Du Bois accurate for all patients?

It performs well for most adults but may be less accurate in extreme obesity, cachexia, or pediatric populations. Other formulas (Mosteller, Haycock) can be considered in those settings.

How often should I re-calculate BSA?

Recalculate whenever weight changes significantly (>5-10%) or before adjusting doses that depend on BSA, such as chemotherapy cycles.

Embed This Calculator

Add this calculator to your website or blog using the embed code below:

<div style="max-width: 600px; margin: 0 auto;"> <iframe src="https://mycalculating.com/category/health-fitness/body-surface-area-du-bois-calculator?embed=true" width="100%" height="600" style="border:1px solid #ccc; border-radius:8px;" loading="lazy" title="Body Surface Area Du Bois Calculator Calculator by MyCalculating.com" ></iframe> <p style="text-align:center; font-size:12px; margin-top:4px;"> <a href="https://mycalculating.com/category/health-fitness/body-surface-area-du-bois-calculator" target="_blank" rel="noopener"> Use full version on <strong>MyCalculating.com</strong> </a> </p> </div>
Open in New Tab

Body Surface Area by Du Bois Formula

Estimate body surface area (BSA) using the Du Bois & Du Bois equation for medication dosing and hemodynamic indexing.

How to use Body Surface Area by Du Bois Formula

Step-by-step guide to using the Body Surface Area by Du Bois Formula:

  1. Enter your values. Input the required values in the calculator form
  2. Calculate. The calculator will automatically compute and display your results
  3. Review results. Review the calculated results and any additional information provided

Frequently asked questions

How do I use the Body Surface Area by Du Bois Formula?

Simply enter your values in the input fields and the calculator will automatically compute the results. The Body Surface Area by Du Bois Formula is designed to be user-friendly and provide instant calculations.

Is the Body Surface Area by Du Bois Formula free to use?

Yes, the Body Surface Area by Du Bois Formula is completely free to use. No registration or payment is required.

Can I use this calculator on mobile devices?

Yes, the Body Surface Area by Du Bois Formula is fully responsive and works perfectly on mobile phones, tablets, and desktop computers.

Are the results from Body Surface Area by Du Bois Formula accurate?

Yes, our calculators use standard formulas and are regularly tested for accuracy. However, results should be used for informational purposes and not as a substitute for professional advice.