BMI Calculator
Enter height and weight in metric or imperial units and get your Body Mass Index with the World Health Organization category. Nothing is stored or sent — close the tab and it is gone.
100% private — everything runs in your browser, nothing is ever uploaded.
How to use it
- Pick metric (cm, kg) or imperial (ft/in, lb).
- Enter your height and weight.
- Read your BMI and the WHO category it falls into.
Why it stays private
Health data is among the most sensitive personal information there is. This calculation needs no server, so it happens entirely in your tab.
Questions
What do the categories mean?
The WHO bands: below 18.5 is underweight, 18.5–24.9 is normal, 25–29.9 is overweight, and 30 or above is obese. The boundaries are the same for adult men and women.
Is BMI accurate for athletes?
Not really. BMI only compares weight to height, so muscular people often land in the overweight band despite low body fat. Treat it as a rough population-level screening number, not a diagnosis.
Does it work for children?
No. Children and teenagers need age- and sex-specific percentile charts — this tool applies the adult bands only.