Measurement guide

Measure the space the package actually fits.

A frame’s advertised size may not match its usable rabbet. Measure the recess that holds the glazing, mat, artwork, and backing before cutting anything.

Measure the finished package

1. Lay the empty frame face-down on a protected, flat surface.
2. Measure between the inner rabbet walls at the back, first horizontally and then vertically.
3. Repeat near the opposite ends. If the frame is not square, use the smaller width and height.
4. Subtract your shop’s fitting allowance so the package can enter without binding.
5. Enter that finished package size—not the catalog size—in the frame cut planner.

Keep the two openings separate

The rabbet opening holds the package at the back. The smaller sight opening is what remains visible from the front. Neither is automatically the finished package size.

Before cutting

• Confirm the frame is assembled and the corners are closed.
• Check for finish buildup, points, liners, or hardware that reduce usable space.
• Test the final dimensions against the actual glazing and backing material.