Polygon miter calculator
Cut angle for joining N flat sides into a regular polygon. Each piece is cut at half the exterior angle measured from a square crosscut.
Miter angle: 30.00°
Interior corner: 120.00°
The formula
Miter angle = 180° / N. Interior corner = 180° × (N − 2) / N. Standard examples: 4 sides = 45°, 6 sides = 30°, 8 sides = 22.5°.