Compound Miter Angle Calculator

Our compound miter calculator determines the exact miter and bevel angles needed to cut crown molding, trim, and other materials at non-90-degree corners. Whether you're dealing with an obtuse corner in a bay window or an odd-angled wall, this tool eliminates the frustrating trial-and-error approach.

Compound miter cuts require setting both the miter (rotation) and bevel (tilt) angles on your saw. The calculations depend on the corner angle and the spring angle of your molding - the angle at which the molding sits against the wall and ceiling. Standard crown molding has a 38-degree spring angle, while some profiles use 45 or 52 degrees.

This calculator is essential for finish carpenters, DIYers installing crown molding, and anyone asking "what angle do I cut crown molding for a 135-degree corner?" or "how do I calculate compound miter angles?" The results work for any corner angle, not just common 90 or 45-degree cuts.