What Do the Interior Angles of a Pentagon Add up To?

By Staff WriterLast Updated Mar 24, 2020 6:20:24 PM ET

The sum of the interior angles of a pentagon is 540 degrees. Each of the five interior angles of a regular pentagon measures 108 degrees.


Pentagons are two-dimensional shapes, characterized by five co-planar sides that are connected to form enclosed figures. A special type of pentagon called regular pentagon, contains 108-degree interior angles, 72-degree exterior angles and an estimated area of 1.72 S2, where "S" denotes the length of a segment.

All pentagons consist of three triangles, where each triangle contains three interior angles that total 180 degrees. The sum of a pentagon's interior angles is taken by multiplying 180 by 3, which is equivalent to 540. In general, the formula for obtaining the sum of all interior angles of any polygon is (n-2) multiplied by 180 degrees, where "n" indicates the number of sides.