Adult BMI Calculator - Body Mass Index
Estimate adult body mass index from height and weight, view standard screening ranges, and understand BMI limitations with this free calculator.
WHAT IS BMI?
Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = kg/m² where kg is a person's weight in kilograms and m² is their height in meters squared.
These category labels follow the CDC's general adult BMI guidance and are intended for adults aged 20 and older. BMI is a screening measure, not a diagnosis, and it does not directly measure body fat or account for factors such as muscle mass, pregnancy, age-related body composition, or individual health history.
Frequently Asked Questions
- What is a healthy BMI?
- For adults aged 20 and older, the standard healthy-weight screening range is generally 18.5 to 24.9. It is not a diagnosis.
- Is BMI accurate for everyone?
- No. BMI does not directly measure body fat and can misclassify people with high muscle mass. Pregnancy, age-related body composition, and individual health history also require different context.
- How often should I check my BMI?
- Checking once a month is usually sufficient.
- Does muscle affect BMI?
- Yes, muscle is denser than fat and can result in a higher BMI.
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