Home › Health & Pets
⚖BMI Calculator (Adults)
CDC BMI categories for adults 20 and older
| BMI | Category |
|---|---|
| Less than 18.5 | Underweight |
| 18.5 to less than 25 | Healthy weight |
| 25 to less than 30 | Overweight |
| 30 to less than 35 | Obesity, class 1 |
| 35 to less than 40 | Obesity, class 2 |
| 40 or greater | Obesity, class 3 (severe) |
Formula
- US units: BMI = 703 × weight (lb) ÷ height (in)²
- Metric: BMI = weight (kg) ÷ height (m)²
Source: Centers for Disease Control and Prevention, Adult BMI Categories. This page is for general information and is not medical advice.
Frequently asked questions
What is a healthy BMI?
For adults 20 and older, the CDC classifies a BMI from 18.5 to less than 25 as healthy weight, 25 to less than 30 as overweight, and 30 or higher as obesity.
Is BMI accurate for athletes or older adults?
BMI is a screening tool, not a diagnosis. It does not separate muscle from fat, so muscular people can show a high BMI, and older adults can have a normal BMI with low muscle mass. Talk to a healthcare provider about your own health.
Can I use this for children or teens?
No. For ages 2 to 19, BMI is compared with CDC growth charts by age and sex (BMI-for-age percentile). Use the CDC's child and teen BMI calculator instead.
More calculators
🐶Dog Age CalculatorDog years → human years$Hourly to Salary CalculatorHourly ↔ yearly, monthly, weekly pay🕘Time Card CalculatorClock in/out → weekly hours & pay⏱Overtime Pay CalculatorTime and a half over 40 hours🧱Concrete CalculatorSlab & post holes → yards and bags🌱Mulch, Soil & Gravel CalculatorArea + depth → cubic yards, bags
Last reviewed: 2026-10-17