Body Mass Index (BMI) is a quick screening tool based on height and weight. It is useful at population level, but it is not a complete picture of individual health.
Formula
BMI = weight (kg) ÷ [height (m)]²
Example: 70 kg and 1.75 m → 70 ÷ (1.75²) ≈ 22.9
Adult categories (WHO)
- Underweight: < 18.5
- Normal: 18.5–24.9
- Overweight: 25–29.9
- Obesity: ≥ 30
Limitations
- Does not distinguish fat from muscle.
- May misclassify muscular athletes or people with higher bone density.
- Does not measure waist fat, blood pressure, lipids, or fitness.
Use BMI as one data point alongside waist measure, activity level, and clinical advice. Try the BMI Calculator and, where relevant, body-fat tools for a fuller view.