BMI Calculator
Free to use, with no sign up. Your entries stay in this browser; calculations run on your device.
Your BMI
Metric: BMI = kg / m². Imperial: BMI = 703 × lb / in². CDC BMI formulas.
Adult BMI categories
| BMI | Category |
|---|---|
| Under 18.5 | Underweight |
| 18.5–24.9 | Healthy weight |
| 25–29.9 | Overweight |
| 30 or above | Obesity |
The bands are commonly written to one decimal place; the exact cutoffs are 18.5, 25 and 30. The result uses your unrounded BMI to choose its band.
BMI is weight for height, not body fat. Adult bands do not apply to children or teens. BMI alone cannot tell you whether you are healthy. Read the CDC explanation of BMI.
For general information only; not medical advice.
How to use this tool
Choose your units, enter your weight and height, then select Calculate BMI. Use total inches for imperial height.
Frequently asked questions
What does BMI measure?
BMI is weight for height, not body fat. It is a screening measure and does not measure muscle, fat distribution or your overall health.
Do these bands apply to children and teens?
No. These adult bands are for people aged 20 and older. Children and teens need BMI interpreted for their age and sex.
Where do the category boundaries fall?
Underweight is below 18.5, healthy weight is 18.5 to below 25, overweight is 25 to below 30, and obesity is 30 or above. The category uses the unrounded BMI.
Can I use pounds and feet?
Choose pounds and inches, then enter your height in total inches. For example, 5 feet 9 inches is 69 inches. Changing units converts your entered measurements.