Find the area, perimeter, interior angle, and apothem of a regular polygon. Enter the number of sides and the side length.
Area
— sq units
Regular polygon.Usage Tip
As the number of sides grows, a regular polygon approaches a circle — its area nears pi times the apothem squared.
THE MATH
interior angle = (n − 2) × 180 ÷ n
area = (1 ÷ 2) × perimeter × apothem
area = (1 ÷ 2) × perimeter × apothem
A regular polygon has equal sides and equal angles.
The apothem is the distance from the center to the midpoint of a side; it acts like the height for the area.
The apothem is the distance from the center to the midpoint of a side; it acts like the height for the area.
Works for any regular polygon with 3 or more sides.
Interior angles grow toward 180 degrees as sides increase.
The apothem depends on the side length and the number of sides.
Interior angles grow toward 180 degrees as sides increase.
The apothem depends on the side length and the number of sides.