Biodiversity Index Calculator - Calculator Academy

Enter the total number of organisms of all species found and the number of species identified into the calculator to determine the Biodiversity Index. This calculator can also evaluate any of the variables given the others are known.

Biodiversity Index Formula

The following formula is used to calculate the Biodiversity Index used by this calculator (a simple species-to-individuals ratio).

BI = S / N

Variables:

BI is the Biodiversity Index (simple ratio used on this page)
N is the total number of organisms (individuals) of all species counted
S is the number of species identified

To calculate this Biodiversity Index, divide the number of species identified by the total number of organisms counted. The resulting quotient is the Biodiversity Index.

What is a Biodiversity Index?

A biodiversity index is a quantitative measure used to assess and compare the diversity of biological species in a given ecosystem, region, or habitat. Many widely used biodiversity indices (such as Shannon and Simpson) consider both the number of species (species richness) and how evenly individuals are distributed among those species (evenness). This page uses a simplified classroom-style index (BI = S/N) based only on total species and total individuals, so it reflects richness relative to sample size and does not by itself measure evenness.

How to Calculate Biodiversity Index?

The following steps outline how to calculate the Biodiversity Index.

First, determine the total number of organisms of all species found (N).
Next, determine the number of species identified (S).
Next, gather the formula from above = BI = S / N.
Finally, calculate the Biodiversity Index.
After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem :

Use the following variables as an example problem to test your knowledge.

total number of organisms of all species found (N) = 500

number of species identified (S) = 20