BMI calculator.
Enter your weight and height to see your body mass index and the adult reference range it falls in. BMI is a rough screening ratio, and this page says what it leaves out.
These tools are free to use without an account.
Estimated body mass index
27.3Falls in the 25.0 to 29.9 reference range for adults.
| WHO adult reference name | BMI |
|---|---|
| Underweight | Under 18.5 |
| Normal weight | 18.5 to 24.9 |
| Overweight | 25.0 to 29.9 |
| Obesity | 30.0 and over |
BMI compares weight with height. It is a fitness estimate, not a diagnosis and not a medical measurement of health. It cannot tell muscle from fat or show where weight is carried, so it can read high for muscular people and low for someone who has lost muscle, and it is less reliable for older adults. Children and teenagers are read on growth charts instead. A doctor can read your result alongside other measures.
Fitness estimates for adults 18 and over, not medical or dietary advice. Results are informational and are not reviewed by a certified personal trainer.
What BMI is
Body mass index divides weight in kilograms by height in metres squared; with pounds and inches the same result is 703 × pounds ÷ inches squared. The World Health Organization groups adult results into reference ranges: under 18.5, 18.5 to 24.9, 25.0 to 29.9 and 30.0 and over. The ranges are population screening tools, which is why this page shows a range and not a verdict.
What BMI cannot tell you
BMI uses only weight and height. It cannot separate muscle from fat, show where fat is carried or measure fitness, so it can read high for someone who lifts and low for someone who has lost muscle. It is less reliable for older adults, and some groups are assessed on different ranges. For body composition, a tape-measure body fat estimate or a check-in photo history tells you more. A doctor can interpret any of these alongside your health history.
Fitness estimates for adults 18 and over, not medical or dietary advice. Results are informational and are not reviewed by a certified personal trainer. Calculations stay in your browser. Typed measurements are not sent or saved.
Common questions.
Is BMI a diagnosis?
No. It is a quick ratio of weight to height that doctors and researchers use to screen populations. It cannot diagnose a condition or measure health, and a result outside a range is a reason to ask a doctor, not a conclusion.
Why can BMI be misleading for people who lift?
Muscle is dense, so a muscular person can weigh more for their height than the ranges expect without carrying extra fat. BMI cannot tell the difference, which is why it can read high for strong, lean people.
Can I use this for a child or teenager?
No. This page is for adults 18 and over. Children and teenagers are assessed with growth charts that account for age and sex, so ask a doctor or school nurse.
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