Calculate your Body Mass Index (BMI) from weight and height, classified per WHO.
WHO ranges: <18.5 underweight · 18.5–24.9 normal · 25–29.9 overweight · ≥30 obese.
Body Mass Index relates your weight to your height and gives a quick indicator of whether you sit in a healthy range. It does not measure fat — it is just a starting point.
You get it by dividing weight in kilograms by the square of height in metres. An adult of 70 kg at 1.75 m has a BMI of about 22.9, which falls in the normal range.
The World Health Organization defines: under 18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, and 30 or above obese.
Not directly. It compares weight and height, so two people with the same BMI can have very different body composition. For a fat percentage, use the body-fat calculator.
For muscular athletes BMI overestimates, because muscle is heavy. For children and teens, separate age-based charts are used instead.
For most adults, a BMI of 18.5 to 24.9. Always alongside other health markers, not on its own.