What is BMI?
Body mass index is weight divided by height squared. It is a simple screening tool used by health organizations to classify weight in adults.
BMI = weight (kg) ÷ height (m)² · BMI = 703 × weight (lb) ÷ height (in)²
BMI categories for adults
| BMI | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Healthy weight |
| 25 – 29.9 | Overweight |
| 30 or more | Obesity |
Limitations
BMI does not distinguish muscle from fat, so very muscular people may show a high BMI. It also does not apply to children, teenagers or pregnant women. It is a starting point, not a diagnosis — talk to a health professional for an individual assessment.
Frequently asked questions
Is BMI the same for men and women?
For adults the same formula and categories are used for men and women.
Can I use this for children?
No. Children and teens use BMI-for-age percentiles, which depend on age and sex.
What is a healthy weight for my height?
The calculator shows the range that corresponds to a BMI between 18.5 and 24.9 for your height.
Results are estimates for information only and are not financial, legal or medical advice. Rates, taxes and fees vary — confirm with a professional or your lender.