UnderweightBelow 18.5
Free adult health tool
Know your BMI. Understand the number.
Enter your height and weight to calculate your body mass index, see your adult BMI category, and get a healthy-weight reference range for your height.
Instant resultMetric and US unitsHealthy-weight range
Your BMI is
23.5Healthy weight
Within the healthy-weight range
Healthy-weight range for your height53.5–72 kg
BMI is a screening measure, not a diagnosis. A healthcare professional can interpret it alongside body composition, medical history, and other factors.
A useful starting point
What your BMI result means
BMI compares weight with height to estimate a weight category. It is quick and widely used, but it does not directly measure body fat or overall health. Treat your result as one piece of a bigger health picture.
Adult BMI chart
BMI categories at a glance
Healthy weight18.5 to 24.9
Overweight25.0 to 29.9
Obesity30.0 or above
Use the result with context
BMI cannot tell the whole story
BMI does not distinguish muscle from fat, show where body fat is stored, or account for every difference in age and body composition. Athletes with more muscle may have a higher BMI without the same health profile as someone with less muscle.
For adults only
People under 20 need a child and teen BMI calculator. Pregnancy can also make adult BMI categories inappropriate.
Review CDC adult BMI categoriesCommon questions
BMI calculator FAQ
What is a healthy BMI?
For adults age 20 and older, the CDC defines a healthy-weight BMI as 18.5 to less than 25. BMI is a screening measure, so it should be considered alongside other health information.
How is BMI calculated?
BMI is weight in kilograms divided by height in meters squared. With US units, the equivalent formula is weight in pounds divided by height in inches squared, multiplied by 703.
Is BMI accurate for everyone?
BMI does not directly measure body fat or distinguish fat from muscle. It can be less informative for some athletes, older adults, pregnant people, and people with certain medical conditions.
Can children use this calculator?
No. This calculator uses adult categories for people age 20 and older. Children and teens need age- and sex-specific BMI percentiles.
Move beyond a single number
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