How to calculate your BMI
- Choose metric or US units.
- Enter your height and weight.
- Read your BMI, its category and the healthy weight range for your height.
BMI categories for adults
| BMI | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 to 24.9 | Healthy weight |
| 25 to 29.9 | Overweight |
| 30 or more | Obesity |
These are the World Health Organization’s categories for adults aged 20 and over, the same for men and women.
What BMI leaves out
BMI was designed in the 1830s to study populations, not individuals. It works reasonably well across large groups but can mislead for one person: muscular people, older adults who have lost muscle, and people of different body shapes can all get a number that doesn’t match their health. Treat it as a starting point for a conversation with a doctor.