Samengestelde Kroonlijst Verstek & Schuine Hoek Calculator

How to use it: enter your crown molding's spring angle (the angle its back makes with the wall - check the profile spec, or a rafter/protractor against an installed sample; 38° and 45° are the two most common) and the wall corner's plan angle (90° for a standard square corner). This gives the compound miter and bevel settings for cutting the molding flat on the saw table, which is how most trim carpenters cut crown - no crown stop or angled fence needed.

Calculation. With spring angle S and corner angle A:

Miter = atan(sin(S) × tan(A/2)), Bevel = asin(cos(S) × sin(A/2))

Worked checks. 38° spring at a 90° corner gives 31.62° miter / 33.86° bevel; 45° spring at a 90° corner gives the classic 35.26° miter / 30° bevel; 52° spring at a 90° corner gives 38.24° miter / 25.81° - all matching commonly published crown-molding cut-angle references.

The result above uses these exact values. This snapshot is included when the page is printed so the output can be checked against the original measurements.

Spring angle

38 deg

Wall corner angle

90 deg

Primary result: Miter angle (saw table): 31.62 deg.

• Measure from the datum or reference edge described by this tool, and do not mix inside, outside and centerline dimensions.
• Keep inputs in the displayed units and preserve more precision than the final cutting or purchasing tolerance requires.
• When the result is close to a limit, verify it with a test piece, field measurement, manufacturer drawing or qualified project professional.

This covers vertical walls meeting at any plan angle - including out-of-square corners and bay-window returns. It does not solve a true sloped/vaulted ceiling transition, where crown runs from a normal wall-ceiling corner up onto a raked ceiling: that is a genuinely different, asymmetric 3D problem (the two sides of the joint aren't mirror images), and this formula does not apply to it. Always cut a test piece from scrap before committing molding.