Interior Angles
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Exterior Angles
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Calculation steps will appear here after you click "Calculate Angles"
About Polygon Angles
Polygons are 2D shapes with straight sides. The angles inside (interior) and outside (exterior) of polygons follow specific rules:
Sum = (n - 2) × 180°
For example, a pentagon (5 sides) has interior angles that sum to (5-2)×180° = 540°.
For regular polygons, each exterior angle is 360° divided by the number of sides.
Irregular polygons have sides and/or angles of different measures.
While the angle sum formulas apply to both, individual angles can only be calculated directly for regular polygons.
Did You Know?
The word "polygon" comes from the Greek words "poly" (many) and "gonia" (angle). The names of polygons are based on Greek numbers combined with "-gon" (e.g., pentagon, hexagon).