What this tool does
Gives the miter angle to cut on each piece when two symmetrical members meet at a corner: 90 degrees minus half the corner angle, with a square cut counted as 0.
How to use it
- Enter the finished corner angle in degrees.
- Run it for the cut angle per piece.
- Cut both members at that same angle.
Worked example
A 90-degree corner needs 90 − 45 = 45 degrees on each piece. A 135-degree corner needs 90 − 67.5 = 22.5 degrees.
Calculation method
Cut angle from square
90-corner/2Frequently asked questions
- Does this match my miter saw’s scale?
- Most miter saws read a square cut as 0, so you can dial in this figure directly. Scales vary, so test on an offcut first.
- What if the corner is not exactly square?
- Real wall corners often are not. Measure the actual angle with a protractor and enter that to get the matching cut.
What this tool does not cover
It assumes two identical symmetrical members. Differing thicknesses, compound cuts needing a bevel angle, and material movement are not reflected.