BMI Calculator

Enter your height and weight to get your BMI and the standard category — underweight, healthy, overweight or obese.

All calculations happen in your browser.

How to use BMI Calculator

  1. Choose metric (kg / cm) or imperial (lb / ft+in).
  2. Enter your height and weight.
  3. Your BMI and category update instantly.

About this tool

Body Mass Index is a simple measure of weight relative to height, used by health professionals as a quick screening tool. The calculator follows the standard World Health Organization categories.

BMI is a general guide, not a diagnosis — it does not distinguish muscle from fat, and it does not apply the same way to children, older adults, athletes or during pregnancy.

Frequently asked questions

What are the BMI categories?
Below 18.5 is underweight, 18.5–24.9 is healthy, 25–29.9 is overweight, and 30 or above is obese. These are the standard WHO ranges for adults.
Is BMI accurate for everyone?
No. It is a rough screening tool and does not account for muscle mass, age, sex or body composition. Talk to a health professional for a full assessment.

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