The Ponderal Index (PI), also known as Rohrer's Index, is a measure of leanness or corpulence. It is calculated as weight divided by height cubed (W/H³). Unlike BMI (W/H²), which scales in two dimensions, PI scales in three, which some researchers believe makes it a more accurate measure for individuals at the very tall or very short ends of the height spectrum.
BMI is widely used but has limitations. For example, it may incorrectly categorize a very tall, lean person as overweight. The Ponderal Index attempts to correct this by using the cube of the height, which better reflects the relationship between mass and volume in the human body. However, BMI remains the more commonly used metric in general health assessments.
This calculator is an informational tool only and is not a substitute for professional medical advice. For a comprehensive assessment of your health and body composition, please consult with a qualified healthcare provider.