Habitat Edge-to-Area Ratio Calculator

Habitat Edge-to-Area Ratio Calculator: Assess Fragmentation

Conservation ecologists use the edge-to-area ratio to judge how fragmented a habitat patch is: a high ratio means proportionally more of the patch is exposed "edge" habitat, vulnerable to outside disturbance, with less protected interior core left for edge-sensitive species.

The Formula

Edge-to-Area Ratio = Perimeter / Area

Worked Example

A habitat patch has a perimeter of 4,000 m and an area of 250,000 m² (25 hectares).

Ratio = 4,000 / 250,000 = 0.016 per meter (moderate edge effect)

How to Use This Calculator

1. Enter the habitat patch perimeter in meters.
2. Enter the habitat patch area in square meters.
3. Click Calculate to get the edge-to-area ratio and fragmentation category.

Related Calculations

Use alongside the Species Richness Index Calculator to relate patch shape to the biodiversity it supports.