Body Mass Index with category breakdown, health risk flags, and trend tracking.
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BMI (Body Mass Index) is calculated by dividing your weight in kilograms by the square of your height in meters. The formula is:
BMI = weight(kg) / height(m)²
The WHO classifies BMI into the following categories:
| Category | BMI Range | Health Risk |
|---|---|---|
| Underweight | < 18.5 | Moderate |
| Normal weight | 18.5 – 24.9 | Low |
| Overweight | 25 – 29.9 | Increased |
| Obese Class I | 30 – 34.9 | High |
| Obese Class II | 35 – 39.9 | Very High |
| Obese Class III | ≥ 40 | Extremely High |
Limitations: BMI does not distinguish between muscle and fat mass. Athletes with high muscle mass may be classified as overweight or obese despite low body fat. For a more accurate assessment, use our Body Fat Calculator.
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