BMI calculator
Body mass index estimates body fat from your height and weight. It's a quick screening number for adults 20 and older, not a diagnosis.
What it means
Adult BMI ranges
- UnderweightBelow 18.5
- Healthy weight18.5 to 24.9
- Overweight25 to 29.9
- Obesity30 or higher
BMI doesn't measure body fat directly and can read high for very muscular people. Your clinician looks at it alongside your waist size, blood pressure and lab results.
About BMI
How is BMI calculated?
BMI is your weight in kilograms divided by your height in meters, squared. In US units, it's 703 times your weight in pounds, divided by your height in inches, squared.
What is a healthy BMI?
For adults, a BMI from 18.5 to 24.9 is in the healthy weight range. Below 18.5 is underweight, 25 to 29.9 is overweight, and 30 or higher is in the obesity range.
Is BMI accurate?
BMI is a quick screening number, not a diagnosis. It doesn't measure body fat directly, so it can read high for muscular people and miss risk in others. A clinician can look at it alongside your waist size, blood pressure and lab results.
Can I use this calculator for children or during pregnancy?
No. This calculator is for adults 20 and older. Children and teens use BMI-for-age percentiles, and BMI isn't used to judge weight during pregnancy.
Know your numbers.
Start a visit by text. Your clinician can order a lipid panel, an A1c or an annual wellness test, and explain what the results mean.
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