Calculate area, perimeter, apothem and angles of any regular polygon given sides and length.
A regular polygon has n equal sides and n equal angles. Area = ½ × perimeter × apothem. Interior angle = (n−2)×180°/n.
Interior Angle
θ = (n−2) × 180° / n
Area
A = ½ × n × s × apothem
The polygon approaches a circle. As n → ∞, the area approaches πr² and the perimeter approaches 2πr.
The exterior angles always sum to 360° for any convex polygon.