BMI Calculator

Calculate BMI, healthy weight range, BMI Prime, and Ponderal Index from height and weight. Private and free.

The BMI Calculator estimates body mass index from height and weight, shows a common adult weight category, and also reports a healthy weight band for your height, BMI Prime, and Ponderal Index. Switch between US and metric units anytime. BMI is a screening number — not a full health assessment. BMI in plain language Body mass index (BMI) compares weight to height. It is widely used as a quick screen for whether someone sits in an underweight, normal, overweight, or obesity range for adults. Ranges can vary by guidelines and age. Adult cutoffs used here follow common World Health Organization (WHO) bands for people age 20 and older. For children and teens, clinicians usually prefer BMI-for-age percentiles instead of adult categories. Adult BMI categories (WHO) These adult categories are used for both men and women age 20+. Your result card maps your BMI into one of these bands.