BMI Calculator

Calculate your Body Mass Index (BMI) from height and weight, in metric or imperial units.

Units

Height (cm)

Weight (kg)

About this tool

The BMI Calculator estimates your Body Mass Index from height and weight, in metric or imperial units. BMI is weight in kilograms divided by height in metres squared.

How to use it

Choose metric (cm, kg) or imperial (feet/inches, pounds).
Enter your height and weight.
Click Calculate BMI and read the result.

Tips and limits

Commonly used adult ranges are under 18.5 (underweight), 18.5–24.9 (normal), 25–29.9 (overweight) and 30 or above (obese). Some health bodies use lower cut-offs for South Asian adults. BMI does not distinguish muscle from fat and is not suitable for children, so treat it as a rough screening number.

Frequently asked questions

Is BMI a diagnosis?

No. It is a simple screening measure. Talk to a doctor about your health.

Is my data saved?

No. It is calculated in your browser.

Does it work for children?

Children and teenagers are assessed differently, so adult ranges do not apply.