Body Mass Index (BMI) is a quick screening measure that compares your weight with your height. Enter your details below to see your BMI, your CDC weight category and the healthy weight range for your height.
BMI categories for adults
- Below 18.5 — Underweight
- 18.5 to 24.9 — Healthy weight
- 25.0 to 29.9 — Overweight
- 30.0 and above — Obesity (class 1: 30–34.9, class 2: 35–39.9, class 3: 40+)
Limits of BMI
BMI does not measure body fat directly. Muscular people can have a high BMI without excess fat, and older adults can have a normal BMI while carrying more fat. Waist size, blood pressure, blood sugar and cholesterol give a fuller picture of your health.
Frequently asked questions
How is BMI calculated?
BMI = weight in kilograms ÷ (height in metres)². In US units: 703 × weight in pounds ÷ (height in inches)².
Can children use this BMI calculator?
No. For children and teens, BMI is compared with age- and sex-specific growth charts. Ask a pediatrician.
What is a healthy BMI?
For most adults, 18.5 to 24.9 is considered the healthy range.
This tool is for general information and does not replace advice from a healthcare professional.