BMI Calculator
Calculate your Body Mass Index and understand what it means for your health
Your BMI Result
About Body Mass Index (BMI)
Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = kg/m2 where kg is a person's weight in kilograms and m2 is their height in meters squared.
BMI is a screening tool that can indicate whether a person is underweight, at a healthy weight, overweight, or obese. However, BMI is not a diagnostic tool. To determine if excess weight is a health risk, a healthcare provider would need to perform further assessments.
BMI Categories:
| BMI Range | Category | Health Risk |
|---|---|---|
| Below 18.5 | Underweight | Possible nutritional deficiency and osteoporosis |
| 18.5 - 24.9 | Normal weight | Low risk (healthy range) |
| 25.0 - 29.9 | Overweight | Moderate risk of developing heart disease, high blood pressure, stroke, diabetes |
| 30.0 and Above | Obese | High risk of developing heart disease, high blood pressure, stroke, diabetes |
Limitations of BMI:
While BMI is a useful screening tool, it has some limitations:
- It may overestimate body fat in athletes and others who have a muscular build
- It may underestimate body fat in older persons and others who have lost muscle
- It doesn't account for differences in body composition between individuals
Frequently Asked Questions
A healthy BMI range is typically between 18.5 and 24.9. This range is associated with the lowest risk of health problems. However, ideal BMI may vary slightly depending on ethnicity and other factors.
BMI is a useful screening tool but has limitations. It may not be accurate for athletes with high muscle mass, pregnant women, the elderly, or children. Always consult with a healthcare provider for a comprehensive health assessment.
For most adults, checking BMI once every few months is sufficient unless you're actively trying to lose or gain weight. Significant changes in weight (more than 5-10% of your body weight) warrant more frequent monitoring.
If your BMI indicates you're overweight or obese, consider consulting a healthcare provider. They can help develop a safe weight management plan that typically includes dietary changes, increased physical activity, and possibly behavioral modifications.
This calculator is designed for adults (age 18+). Children and teens need BMI calculations that account for their age and sex-specific growth charts. Pediatric BMI calculators use percentiles rather than fixed categories.