polygon with eight sides

An octagon or 8-gon is a shape with 8 sides and 8 corners.

An octagon

Regular octagonEdit

All sides of a regular octagon are the same length. Each corner is 135°. All corners added together equal 1080°.


The amount of space a regular octagon takes up is


a is the length of one of its sides.

Another way to write it is



Related pagesEdit