Regular Polygons Calculator


Show values to . . . significant figures.
number of edges
(3 to 1000)
length of edgeunits Polygon
area square units
in-radiusunits
circum-radius units

Extra Information

A regular polygon is one which has all its edges the same length, and all its vertex angles the same size. The circumcircle is the circle drawn around the outside of the polygon so as to touch all its vertices (or corners). Its radius is the CIRCUM-radius. The incircle is the circle drawn around the inside of the polygon so as to touch all its edges. Its size is given here by the IN-radius. Polygons are named by the number of edges (or vertices) they have. Some of the most commonly used names are:

Edges  Name
3 triangle
4 quadrilateral
5 pentagon
6 hexagon
7 heptagon
8 octagon
9 nonagon
10 decagon
11 undecagon
12 dodecagon