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  1. Home
  2. Health & Fitness
  3. Body Surface Area Calculator

Body Surface Area Calculator

Calculate your Body Surface Area (BSA) using multiple medical formulas. BSA is used for drug dosing, cardiac calculations, and metabolic assessments.

Formula:BSA = √(Height × Weight / 3600)

Body Surface Area

BSA

1.948 m²

Dubois formula

Average (All Formulas)1.956 m²
Comparison to Standard112.6% of 1.73 m²

Body Surface Area

BSA

1.948 m²

Dubois formula

Average (All Formulas)1.956 m²
Comparison to Standard112.6% of 1.73 m²

Formula Selection

Measurements

Formula Comparison

FormulaDescriptionBSA (m²)
DuBoisMost widely used (1916)1.9480
MostellerSimple & accurate (1987)1.9515
HaycockGood for children (1978)1.9577
GehanGehan & George (1970)1.9616
BoydBoyd formula (1935)1.9603

Average BSA: 1.956 m²Range: 1.948 - 1.962 m²

BSA Formulas

DuBois & DuBois (1916):

BSA = 0.007184 × W^0.425 × H^0.725

Mosteller (1987):

BSA = sqrt((H × W) / 3600)

Haycock (1978):

BSA = 0.024265 × W^0.5378 × H^0.3964

W = weight in kg, H = height in cm

BSA Reference Values

CategoryBSA Range (m²)
Newborn0.2 - 0.25
Child (2 years)0.5 - 0.55
Child (9 years)1.0 - 1.1
Adult Female (average)1.6 - 1.8
Adult Male (average)1.7 - 2.0

Standard reference BSA: 1.73 m² (used in medical calculations)

Medical Applications of BSA

Drug Dosing

Chemotherapy drugs are often dosed in mg/m² for more accurate dosing across different body sizes.

Cardiac Index

Cardiac output divided by BSA gives cardiac index, allowing comparison between individuals.

GFR Standardization

Glomerular filtration rate is often standardized to 1.73 m² BSA for comparison.

Burn Assessment

Burn area is calculated as percentage of total BSA to determine treatment.

BSA Scenarios

Explore how changes affect your results

Your BSA vs Population

Compared to the general population

Your BSA

1.948 m²

Percentile

69th

There's room for improvement

Distribution

You

Small

1.500

Below Avg

1.650

Average

1.800

Above Avg

2.000

Large

2.200

Your Ranking

Top 69%

31% are higher

BSA Information

Based on your results

0/4 completed
⚕️ MedicalRecommended

Your BSA Value

Your body surface area is 1.948 m², which is 113% of the standard 1.73 m² reference value.

⚕️ MedicalRecommended

Drug Dosing Implications

BSA-based drug dosing helps ensure accurate medication amounts for your body size.

⚕️ MedicalOptional

Formula Selection

The DuBois and Mosteller formulas are most commonly used for adults.

Quick Answer

BSA (Body Surface Area) is used for drug dosing, especially chemotherapy. Du Bois formula: BSA = 0.007184 × Height^0.725 × Weight^0.425. Average adult BSA: 1.7 m² (women) to 1.9 m² (men).

Key Facts

  • Used for medication dosing, especially chemo
  • Du Bois formula most common
  • Mosteller formula simpler alternative
  • Average adult: 1.7-1.9 m²
  • More accurate than weight alone for dosing
  • Multiple formulas may give slightly different results

Frequently Asked Questions

Body Surface Area (BSA) is the measured or calculated surface area of a human body, expressed in square meters (m²). It's used in medicine for drug dosing (especially chemotherapy), determining cardiac index, and calculating metabolic rates.

Total surface area of the body in m². Used for drug dosing and medical calculations.

BSA correlates better with metabolic mass than body weight alone. Many drugs, especially chemotherapy agents, are dosed per m² of BSA for more accurate dosing across different body sizes. It's also used to calculate cardiac output and renal function.

Better correlates with metabolism than weight. Used for accurate drug dosing, especially chemotherapy.

Average adult BSA is approximately 1.7-2.0 m² for men and 1.6-1.8 m² for women. A "standard" adult BSA of 1.73 m² is often used as a reference value. Children have proportionally larger BSA relative to weight.

Men: 1.7-2.0 m². Women: 1.6-1.8 m². Standard reference: 1.73 m².

DuBois is the most widely used and accepted. Mosteller is simpler and equally accurate for most adults. Haycock is preferred for pediatric patients. The choice often depends on institutional preference and patient population.

DuBois most common. Mosteller equally accurate, simpler. Haycock preferred for children.

BSA and BMI are different measures. BMI uses weight/height² and indicates weight status. BSA estimates actual skin surface area. A tall, lean person and a short, heavy person might have similar BSA but very different BMIs.

Different measures. BMI indicates weight status. BSA estimates skin surface area.

Body Surface Area

BSA

1.948 m²

Dubois formula

Average (All Formulas)1.956 m²
Comparison to Standard112.6% of 1.73 m²

Medical Disclaimer

This calculator is for informational purposes only and should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult with a qualified healthcare provider before making any health-related decisions.