Geometry · interactive lab

Regular polygon explorer

Explore the interior angles, diagonals, perimeter, and area of regular polygons.

Regular polygon explorerLIVE EXPLORATION
Change a value to see the connection

Your measurements

A regular polygon has equal sides and equal interior angles. The diagram uses a normalized scale.

Why it works

Interior angle = (n − 2) × 180° / n
    A little question. A clearer picture.

    Regular polygon explorer: common questions

    Wondering about the why? Start here.

    What makes a polygon regular?

    A regular polygon has equal side lengths and equal interior angles. This explorer uses that assumption for its diagram, individual angles, apothem, and area. Equal side lengths alone do not make every polygon regular.

    Learn about polygon angles
    How do I calculate a regular polygon’s interior angle?

    For n sides, each interior angle is (n − 2) × 180° / n. A regular hexagon has six sides, so each angle is 120°. The interior-angle sum of any simple polygon with n sides is (n − 2) × 180°.

    Work through the angle formula