Body mass index (BMI) compares your weight to your height. It is a quick screening number used by doctors and researchers, but it is not a diagnosis.
BMI Calculator
Fill in the form to see your estimate. Nothing you enter is stored or sent anywhere.
Estimates only, based on population equations. Not medical advice. If you are pregnant, under 18, have a medical condition or take medication that affects weight or appetite, check with a qualified healthcare professional.
BMI categories for adults
| BMI | Category |
|---|---|
| Below 18.5 | Underweight range |
| 18.5–24.9 | Healthy weight range |
| 25.0–29.9 | Overweight range |
| 30.0 and above | Obesity range |
What BMI can’t tell you
- It does not distinguish fat from muscle, so muscular people can score “overweight”.
- It does not show where fat is stored. Waist size is a useful extra check.
- Different cut-offs are often used for some ethnic groups, including people of Asian heritage.
- It is not designed for children, pregnant women or very elderly people.
If your BMI is outside the healthy range, it is a reason for a conversation with your doctor, not a verdict. For a practical next step, use the calorie calculator or the goal timeline.