Find each interior angle from the number of polygon sides
Result
Interior Angle
Step-by-Step Derivation
Regular Polygon Interior Angle Formula
Interior angle = ((n - 2) × 180°) / n
A polygon with n sides can be divided into n-2 triangles, so its interior angle sum is (n-2)180 degrees. For a regular polygon, all angles are equal, so divide by n.
⚠The number of sides must be an integer at least 3. This calculator assumes the polygon is regular.
How Polygon Interior Angles Work
Interior angles are the angles inside a polygon. Regular polygons have equal sides and equal angles, making the per-angle formula possible.
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