BMI Calculator

Calculate Body Mass Index from height and weight, in metric or imperial units.

Formula

BMI = weight(kg) / height(m)²

Tips

BMI is a population-level screening measure, not a diagnosis or a measure of health.
It does not distinguish muscle from fat, so it misclassifies athletes and very muscular people.
It is also less applicable to children, pregnant people, and older adults, and its thresholds vary across ethnic groups.
Treat any result as a prompt for a conversation with a clinician rather than a conclusion in itself.

Frequently asked questions

Is BMI a reliable measure of health?

On its own, no. It is a cheap and quick population-level indicator. Waist circumference, body composition, blood markers, fitness, and clinical history all say considerably more about an individual’s health than BMI does.