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Regular Polygon Calculator

Area, perimeter, angles for any regular polygon.

Regular Hexagon
Area
259.808
Perimeter
60.000

Geometry

Interior angle: 120.00°
Exterior angle: 60.00°
Sum of interior: 720°
Apothem: 8.660
Circumradius: 10.000

For regular polygons (all sides and angles equal). Area = (n × s × a) / 2, where a is the apothem (distance from center to midpoint of a side). Apothem = s / (2 tan(π/n)).

About

Enter the number of sides and the side length of a regular polygon. Get area, perimeter, interior angle, exterior angle, apothem, and circumradius. Works for triangles, hexagons, octagons, and any n-gon up to 100.

How to use

  1. Enter number of sides.
  2. Enter side length.
  3. Read area, perimeter, and angles.

FAQ

Does this work for irregular polygons?+

No. For irregular shapes, use the shoelace formula on the vertex coordinates instead. This tool assumes all sides equal and all interior angles equal.