Identify the included angle
Ask whether the angle in the drawing is the angle between the two parts or the angle shown on the saw. For a symmetrical miter joint, the two miter cuts divide the included angle.
Mark reference faces before a batch
Label the inside, outside, show face, and direction on every part. This prevents mirrored cuts, which are more common than a math error once the saw is set correctly.
Verify with matching scrap
Cut a short test pair from similar stock, assemble it dry, and confirm the joint and overall form before committing the finished pieces.
Shop 101
Apply this reference to your project
Use your own project measurements and record how the result affects the material, setup or estimate.
- Name the material, dimension, or cost input that affects the decision.
- Use the reference and related calculator to check the measurement or estimate.
- Test or compare the result before committing final material, time, or client scope.
Related tools & lessons
Common questions
How do I calculate a miter cut?
For a symmetrical miter joint, divide the included angle between the two pieces, then verify the setting with a scrap test because the saw's reference and part orientation matter.
Why does my miter joint have a gap?
Common causes include an incorrect reference face, a mirrored part, an uncalibrated saw, stock that is not flat, or using a design angle as if it were the saw setting.
Is a miter cut the same as a compound miter?
A miter cut rotates the saw left or right. A compound miter combines miter rotation with blade bevel, so it needs additional setup information.