Calculate your body mass index
BMI is a quick screening number that relates your weight to your height. It won't tell the whole story — it can't distinguish muscle from fat — but it's a widely used starting point for thinking about a healthy weight range. This calculator works in both metric and imperial units and places your result on the standard categories.
How to use it
- Choose metric or imperial units.
- Enter your height and weight.
- Read your BMI and the category it falls in.
How to read it
- The standard bands run from underweight through a healthy range to overweight and above.
- BMI is a population-level guide, not a diagnosis.
- Very muscular people often read high despite low body fat.
Questions people ask
Is BMI accurate for everyone? It's a rough guide. Athletes, older adults, and some body types are poorly described by it, so treat it as one signal among several.
Is my data stored? No — the calculation runs locally in your browser.