BMI & BSA Calculator
Calculate Body Mass Index with Asian Indian cutoffs (WHO Asia-Pacific) and Body Surface Area (Mosteller / DuBois) — used by doctors across India for diagnosis and drug dosing.
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BMI
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Category
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Ideal Body Weight
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Asian Indian BMI Cutoffs (WHO Asia-Pacific):
- • Underweight: < 18.5
- • Normal: 18.5 – 22.9
- • Overweight: 23 – 24.9
- • Obese Class I: 25 – 29.9
- • Obese Class II: 30 – 34.9
- • Obese Class III: ≥ 35
Want BMI & BSA auto-calculated in patient records?
SmartClinic India captures vitals automatically and computes BMI, BSA, and ideal weight in every OPD visit.
About BMI & BSA
Body Mass Index (BMI) is calculated as weight (kg) divided by height squared (m²). It's the global standard for classifying underweight, normal weight, overweight, and obesity. For Asian Indians, stricter cutoffs apply because of higher body fat percentage and central adiposity at lower BMI values — leading to earlier risk of diabetes, hypertension, and heart disease.
Body Surface Area (BSA) is used for accurate drug dosing in chemotherapy, pediatrics, and intensive care. The Mosteller formula is preferred for daily clinical use, while DuBois remains common in research and oncology protocols.
Frequently Asked Questions
What is the normal BMI for Indians?
18.5–22.9 kg/m² is considered normal for Asian Indians (WHO Asia-Pacific). 23 and above is overweight.
Why are Indian BMI cutoffs lower?
Indians have higher visceral fat and metabolic risk at lower BMI, so guidelines flag risk earlier than global WHO cutoffs.
When is BSA needed in clinical practice?
BSA is essential for chemotherapy dosing, pediatric drug calculation, cardiac index (CI = CO/BSA), and burns assessment.