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BMI — Body Mass Index
Weight-for-height index used for nutritional assessment and obesity classification
Weight
Height
—
BMI kg/m²
1618.525303540+
Weight used: — kg | Height used: — m
WHO BMI Classification
| BMI (kg/m²) | Category | Health Risk |
|---|---|---|
| <16.0 | Severe thinness | Very high |
| 16.0–16.9 | Moderate thinness | High |
| 17.0–18.4 | Mild thinness | Moderate |
| 18.5–24.9 | Normal weight | Average |
| 25.0–29.9 | Overweight (Pre-obese) | Increased |
| 30.0–34.9 | Obese Class I | Moderate |
| 35.0–39.9 | Obese Class II | Severe |
| ≥40.0 | Obese Class III (Morbid) | Very severe |
BMI = Weight (kg) / Height (m)²
Conversions: lbs ÷ 2.2046 = kg | (ft × 30.48) + (in × 2.54) = cm
Conversions: lbs ÷ 2.2046 = kg | (ft × 30.48) + (in × 2.54) = cm
Limitations: BMI does not distinguish fat from muscle mass. Athletes may have elevated BMI without excess fat. In elderly, a BMI of 23–27 may be protective. In Asian populations, overweight threshold is often set at 23.0 kg/m².
For clinical decision support only. Not a substitute for professional medical judgment.
