Formula: BMI = weight (kg) / height (m)²
Body Mass Index is calculated by dividing your weight in kilograms by the square of your height in meters. For Imperial units: BMI = (weight in lbs × 703) / (height in inches)². BMI is a screening tool, not a diagnostic — it doesn't account for muscle mass, bone density, or body composition.
| BMI Range | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Normal weight |
| 25.0 – 29.9 | Overweight |
| 30.0 – 34.9 | Obese (Class I) |
| 35.0 – 39.9 | Obese (Class II) |
| 40.0 and above | Obese (Class III) |