What is the interior angle of a 12- sided shape?

The total interior angle of a 12 sided polygon is = (12 - 2) 180 degrees = 1800 degrees. The internal angle at each vertex of an regular dodecagon is equal to = = 150 degrees. While the exterior angle at a single vertex is = = 30 degrees. The total exterior angle of a 12 sided polygon is 360 degrees.