Primary CareMetabolicClinicians & PublicPublic Domain
BMI & BSA Calculator
Body Mass Index & Body Surface Area Calculator
Standardized anthropometric screening tool for classifying adult weight categories and dosing medications.
2 items·Estimated time: ~1 min·Evidence references below
Clinical Formula Calculator
BMI & BSA Calculator Parameters
About the BMI & BSA Calculator
Clinical calculator for Body Mass Index (WHO/CDC) and Mosteller Body Surface Area.
Scoring Methodology & Interpretation
The BMI & BSA Calculator uses a validated formula algorithm with predefined clinical cutoffs established in peer-reviewed derivation and validation cohorts:
| Score Range | Severity Classification | Clinical Interpretation |
|---|---|---|
| 0 – 18.4 | Underweight | BMI below standard healthy population range. |
| 18.5 – 24.9 | Normal Weight | Standard adult healthy weight range. |
| 25 – 29.9 | Overweight | Modestly increased risk of cardiometabolic conditions. |
| 30 – 34.9 | Class I Obesity | Elevated risk of chronic metabolic complications. |
| 35 – 39.9 | Class II Obesity | Substantially increased cardiovascular and metabolic risk. |
| 40 – 100 | Class III Obesity | Severe obesity associated with substantial morbidity. |
Clinical Pearls & Considerations
- Mosteller Body Surface Area (BSA = √[height(cm) × weight(kg) / 3600]) is widely used in oncology chemotherapy dosing and hemodynamics.
Copyright & Intellectual Property Attribution:
World Health Organization (WHO) and Mosteller formula. Public domain formulas.
License: Public Domain
Clinical Disclaimer & Scope of Use
This instrument is designed for educational, informational, and clinical reference purposes. Screening scores do not constitute a definitive medical diagnosis. Individual clinical management must integrate full diagnostic history, physical examination, and laboratory data by a licensed healthcare professional.
- BMI does not distinguish adipose tissue from muscle mass, bone density, or fluid retention.
- Cutoffs may differ in Asian populations (where overweight is often defined at ≥ 23 kg/m²).
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Evidence & Primary Literature Citations
- Key Validation StudySimplified calculation of body-surface area.Mosteller RD. N Engl J Med. 1987;317:1098.
- Appropriate body-mass index for Asian populations and its implications for policy and intervention strategies.WHO Expert Consultation. Lancet. 2004;363:157-163.