Estimate adult body mass index from height and weight and see the corresponding CDC screening category.
Calculate your estimate
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How this calculator can help
BMI offers a quick starting point for discussing weight-related health. It is a screening measure, not a diagnosis, and it does not directly measure body fat or account for muscle mass, pregnancy, age-related changes, or every individual difference.
How the estimate works
BMI equals weight in kilograms divided by height in metres squared. For adults age 20 and older, the CDC categories are: underweight below 18.5, healthy weight 18.5 to below 25, overweight 25 to below 30, and obesity 30 or above.
Sources and methodology
We use transparent formulas and primary public-health or research sources. Calculators simplify real life, so their results should be interpreted as estimates.