Compound Miter Calculator for Woodworkers
Saw settings in degrees, not useless decimals. Enter your corner and tilt angles.
Miter Angle
39.7°
Set your miter gauge to 39.7°
Blade Tilt
29.2°
Tilt your blade to 29.2°
Complementary Miter
50.3°
If your saw reads from the fence
Complementary Tilt
60.8°
If your saw tilts the other way
Cut Diagram
What is a compound miter angle?
A compound miter involves two simultaneous angle cuts: the miter angle (across the face of the board) and the blade tilt or bevel (through the thickness). You need both when joining pieces that meet at a corner AND are tilted — like crown molding, picture frames with sloped profiles, or any angled joinery where the pieces aren't flat.
How to use these settings
- Measure your corner angle (90° for standard walls).
- Measure or look up the tilt/spring angle of your material.
- Enter both values above and press Calculate.
- Set your miter saw gauge to the Miter Angle value.
- Tilt your blade to the Blade Tilt value.
- If your saw reads differently, use the complementary angles.
Common mistakes
- Confusing spring angle with tilt angle. Crown molding spring angles (38° or 45°) are measured from the wall. Make sure you enter the correct value for your material.
- Forgetting inside vs. outside corners. Check the "Outside corner" box for outside corners — the cut direction reverses.
- Not testing on scrap wood first. Always make a test cut on scrap before cutting your actual material.
Frequently asked questions
- What is a compound miter angle?
- A compound miter combines two angle cuts: the miter (across the face of the board) and the bevel or blade tilt (through the thickness). You need both when joining pieces that meet at a corner and are tilted, like crown molding or sloped picture frames.
- What angles do I need for crown molding at a 90° corner?
- For 52/38 crown (the most common): set your miter to 38.2° and bevel to 31.6°. For 45/45 crown: both miter and bevel are 35.3°. See the crown molding angle chart for a quick reference.
- What is a complementary angle?
- Some miter saws read the angle from the fence (not the blade). If yours does, use the complementary angle: 90° minus the calculated value. This calculator shows both so you can use whichever matches your saw.
- How do I cut an outside corner?
- Check the "Outside corner" box. The miter and bevel values stay the same magnitude, but the cut direction reverses. The long point of the cut moves to the front (visible side) of the workpiece instead of the back.