BMI Calculator
Calculate your Body Mass Index and get personalized health insights
Calculate Your BMI
Your Results
Enter your measurements to calculate BMI
What is BMI?
Body Mass Index (BMI) is a measure of body fat based on height and weight. It's a simple screening tool used to categorize weight status and estimate health risk. BMI is calculated using a person's weight and height and is expressed as a number (kg/m²).
BMI Formula
BMI = weight (kg) / height (m)²
or
BMI = (weight (lbs) / height (inches)²) × 703
The metric formula uses kilograms and meters, while the imperial formula uses pounds and inches.
BMI Categories
| BMI Range | Category | Health Risk |
|---|---|---|
| < 18.5 | Underweight | Increased risk |
| 18.5 - 24.9 | Normal Weight | Low risk |
| 25.0 - 29.9 | Overweight | Moderate risk |
| 30.0 - 34.9 | Obesity Class I | High risk |
| 35.0 - 39.9 | Obesity Class II | Very high risk |
| ≥ 40.0 | Obesity Class III | Extremely high risk |
Important Notes
- BMI is a screening tool, not a diagnostic measure. It doesn't directly measure body fat.
- BMI may overestimate body fat in athletes and muscular individuals.
- BMI may underestimate body fat in older adults and those who have lost muscle mass.
- For children and teens, BMI is age and sex-specific and interpreted differently.
- Consult with a healthcare professional for a comprehensive health assessment.