Body Surface Area Calculator

Category: Other Health

- April 07, 2025

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Body Surface Area (BSA) is used in medicine for determining drug dosages, assessing metabolic rates, and evaluating organ function. This calculator provides BSA values using multiple formulas for medical reference.

Patient Information

Height:

Weight:

Patient Type:

Gender:

Advanced Options

Preferred Formula:

Decimal Places:

BSA Calculation Results

Formula Comparison

Formula	BSA (m²)	Year	Best For

Visual Comparison

Calculation Method

Clinical Applications

Drug Dosing

Many medications, especially chemotherapy drugs, are dosed based on BSA to optimize efficacy while minimizing toxicity.

Cardiac Index

Cardiac output divided by BSA gives the cardiac index, a hemodynamic parameter standardized for body size.

Burn Assessment

BSA is used to calculate the percentage of body affected in burn patients and determine fluid requirements.

Renal Function

Glomerular filtration rate is often reported relative to BSA to standardize kidney function across different body sizes.

What Is the Body Surface Area Calculator?

The Body Surface Area (BSA) Calculator helps estimate the total external surface area of the human body based on height and weight. BSA plays an important role in clinical settings, especially for determining appropriate drug dosages and evaluating vital organ functions.

This BSA measurement tool uses various established formulas to provide accurate results across different body types and age groups. It's useful for healthcare professionals, patients, and anyone interested in health metrics like total daily energy expenditure (TDEE), renal function, and chemotherapy dosing.

Body Surface Area Formulas

The calculator can apply different equations to estimate BSA. Here's a sample of the formulas it uses:

DuBois & DuBois Formula:
BSA = 0.007184 × weight^0.425 × height^0.725

Mosteller Formula:
BSA = √(height × weight ÷ 3600)

Haycock Formula:
BSA = 0.024265 × weight^0.5378 × height^0.3964

Each formula is selected based on patient type (adult, pediatric, or infant) and known reliability for specific body profiles.

How to Use the BSA Calculator

Using the calculator is simple and takes just a few steps:

Enter your height and weight. Choose between cm/inches and kg/pounds.
Select your patient type (adult, pediatric, or infant) and gender.
Choose whether to see a single formula result or compare all formulas.
Click "Calculate BSA" to view your result.
The tool also provides a percentile comparison and optional clinical context.

Why Body Surface Area Matters

BSA is more accurate than weight alone in many medical calculations. It influences:

Drug dosing – especially chemotherapy and other precise treatments
Cardiac Index – helps interpret heart function relative to body size
Burn assessments – estimates affected body area for treatment planning
Kidney function – used in glomerular filtration rate (GFR) estimation

These applications make BSA a key metric alongside others like TDEE estimation, protein intake guidelines, and carbohydrate intake tools.

Benefits of Using This Tool

Applies multiple formulas for accurate comparison
Works for adults, children, and infants
Includes a visual chart and percentile rankings
Helpful for clinical insight or personal health tracking

Frequently Asked Questions (FAQ)

What units should I use?

You can input height in cm or inches, and weight in kg or pounds. The tool automatically converts units as needed.

Which formula is the most accurate?

That depends on the user. The Mosteller formula is simple and widely used, while Haycock and Boyd are often better for pediatric patients. The calculator recommends the best formula based on your selection.

Is this calculator only for medical professionals?

No. While it’s helpful in clinical settings, anyone interested in health metrics like TDEE, body type classification, or drug dosing guidance may find it useful—just like those using a GFR calculator or a Chipotle calorie breakdown tool.

Can I use this for chemotherapy dosing?

Yes. Chemotherapy drugs are often dosed using BSA. This tool includes a quick view of your chemotherapy dosing relative to a standard BSA of 1.73 m², similar to what you’d find in a Carboplatin dosage guide.

Is this similar to BMI?

Not exactly. BMI uses weight and height to estimate body fat. BSA, on the other hand, calculates surface area and has more clinical applications, such as being a component in energy expenditure guides or organ function analysis.

Who Can Use This Calculator?

This BSA calculator can benefit:

Doctors and nurses calculating drug dosages or assessing cardiac index
Pharmacists cross-checking chemotherapy plans
Patients interested in energy or nutrition metrics
Health-conscious users exploring metrics like macro breakdowns or protein requirements

Additional Resources You Might Like

TDEE Calculator – Estimate your daily calorie needs
Protein Calculator – Calculate your optimal protein intake
GFR Calculator – Assess kidney function with ease
Chipotle Nutrition Calculator – Customize your order and track your macros
Sobriety Calculator – Track days sober and stay motivated

Whether you’re looking to calculate body surface area for clinical precision or personal insight, this calculator offers a straightforward, informative experience—making it a useful addition alongside tools like the BAC estimation tool, the body type calculator, and the paracetamol dose guide.