# Ponderal Index (Corpulence Index) Calculator

## What is Ponderal Index (also known as Corpulence Index)?

Ponderal Index is a ratio of a person’s height to weight.
While it can apply to people of any age, it is typically used in Pediatrics (Children and Babies) to assess the ratio of height to weight of a person.

## How to Calculate Ponderal Index

In pounds and inches (imperial scale), Ponderal Index is calculated as:
$\frac{\text{Height(inches)}}{\sqrt[3]{\text{Mass (pounds)}}}$
In meters and kilograms (metric scale), Ponderal Index is calculated as:
$\frac{\text{Mass (kg)}}{\text{Height (m)}^3}$

## Example

Example 1:
A person has a mass of 165 lbs and is 5 foot 10 inches (70 inches) tall.
$\text{Ponderal Index}=\frac{70}{\sqrt[3]{165}}$
$\text{Ponderal Index}=\frac{70}{4.1213}$
$\text{Ponderal Index}=16.98$
This person’s Ponderal Index is 16.98
Example 2:
A person has a mass of 75kg and is 1m 78cm (1.78m) tall.
$\text{Ponderal Index}=\frac{75}{1.78^3}$
$\text{Ponderal Index}=\frac{75}{5.6398}$
$\text{Ponderal Index}=13.29$
This person’s Ponderal Index is 13.29

## Challenges with Ponderal Index

Like all “simple” health calculators (such as BMI), Ponderal Index is an indicator of health (among a number of other factors) not an absolute measurement.
Some challenges with Ponderal Index include:
– It does not show a difference between people with lots of muscle and lots of fat – a very muscly person may have the same BMI as a person with a lot of fat.
– It does not show a difference between body types that may hold weight in different parts of their bodies
It is important to remember that Ponderal Index is an indicator and not an absolute measurement of health.