What's Your Body Mass Index?
Enter your height and weight to instantly calculate your BMI, see your category, and find your healthy weight range.
BMI Categories
| Category | BMI Range |
|---|---|
| Underweight | < 18.5 |
| Normal weight | 18.5 – 24.9 |
| Overweight | 25.0 – 29.9 |
| Obese (Class I) | 30.0 – 34.9 |
| Obese (Class II) | 35.0 – 39.9 |
| Obese (Class III) | ≥ 40.0 |
Frequently Asked Questions
What is BMI?
BMI (Body Mass Index) is a measure of body fat based on height and weight. It's calculated as weight in kg divided by height in metres squared (kg/m²). It's a quick screening tool used worldwide.
What is a healthy BMI?
A BMI between 18.5 and 24.9 is considered healthy. Below 18.5 is underweight, 25-29.9 is overweight, and 30+ is obese. These ranges apply to adults over 18.
Is BMI accurate for athletes?
BMI can be misleading for muscular people because it doesn't distinguish between muscle and fat. A bodybuilder may have a "overweight" BMI but very low body fat. Consider using body fat percentage or waist circumference as additional measures.
Can BMI predict health risks?
BMI correlates with risk of type 2 diabetes, heart disease, and certain cancers at the population level. However, it's not a diagnostic tool — factors like waist circumference, blood pressure, and cholesterol are also important.