Results are estimates. Not professional advice.
Standard BMI Classifications
As defined by the World Health Organization (WHO) for adults over 20.
| Category | BMI Range (kg/m²) | Health Risk |
|---|---|---|
| Underweight | < 18.5 | Nutritional deficiency risk |
| Healthy Weight | 18.5 – 24.9 | Lowest risk of disease |
| Overweight | 25.0 – 29.9 | Increased metabolic risk |
| Obese (Class I) | 30.0 – 34.9 | High cardiovascular risk |
| Obese (Class II) | 35.0 – 39.9 | Very high health risks |
Understanding Body Mass Index (BMI)
Body mass index (BMI) is a measure of body fat based on height and weight that applies to adult men and women. It is a simple tool that helps health professionals estimate whether a person is at a healthy weight, underweight, overweight, or obese.
While BMI is a useful screening tool, it has limitations. It does not directly measure body fat and does not account for muscle mass, bone density, or overall body composition. For example, athletes with high muscle mass may have a high BMI score despite having low body fat.
Why BMI Matters
Maintaining a healthy BMI is associated with lower risks for various health conditions, including Type 2 diabetes, high blood pressure, and cardiovascular diseases. Our calculator uses the standard formula: Weight (kg) / Height² (m).