Compound miter calculator
Calculate blade tilt and miter angle for crown molding and other compound cuts.
°
38° or 45° most common°
90° for square cornersCross-section — spring angle
Plan view — corner & miter
Miter angle
31.6°
Set on fence/turntable
Blade tilt
33.9°
Bevel from vertical
Common crown molding setups
Profile
Miter
Tilt
38° @ 90° corner
31.6°
33.9°
45° @ 90° corner
35.3°
30.0°
38° @ 135° corner
14.0°
39.8°
How Compound Miters Work
Crown molding sits at an angle between the wall and ceiling — the spring angle. To cut a joint at a corner, you need two angles set on the saw simultaneously: the miter angle (turntable/fence setting) and the blade tilt (bevel setting).
Most crown molding is either 38° or 45° spring angle. The most common corner is 90° (square). For non-square corners (bay windows, angled walls), measure the actual corner angle and enter it here.
Tips
- Check the spring angle on the molding profile — it's printed on the back of most stock
- Always cut test pieces from scrap before cutting the real material
- For outside corners, reverse the miter angle direction
- Measure actual corner angles with a digital protractor — walls are rarely exactly 90°
These calculators are provided for estimation and educational purposes only.