BMI Calculator
Calculate your Body Mass Index and see the healthy-weight category.
Body Mass Index is a quick screening number that relates your weight to your height: weight in kilograms divided by height in metres squared. It won't distinguish muscle from fat, but as a population-level indicator it's the standard first check for whether someone falls in the underweight, healthy, overweight or obese range.
Enter your height and weight — in metric or imperial units — and this calculator returns your BMI and the category it falls into, with the standard WHO thresholds. It runs entirely in your browser, so your measurements stay private.
How to use BMI Calculator
- 1
Choose your units
Metric (kg, cm) or imperial (lb, in).
- 2
Enter height and weight
The BMI updates instantly.
- 3
Read your category
Underweight, healthy, overweight or obese.
Features
- Metric and imperial units
- WHO standard category thresholds
- Private — nothing leaves your browser
Frequently asked questions
Common mistakes to avoid
- Mixing units — entering height in cm but weight in pounds gives a nonsensical result.
- Treating BMI as a health verdict rather than a screening indicator.
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