Geometry Foundational

Perimeter Calculator

Select a shape and enter its dimensions to find the perimeter and area. Supports triangles, rectangles, squares, regular polygons (3–12 sides), and irregular polygons up to 6 sides.

5 shape types
Area computed too
Labeled shape diagram
Inputs
Area computed via Heron's formula.
Apothem and area also computed.
Result
Select a shape and enter dimensions.
Step-by-Step Solution
Diagram
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