The thrifter’s field guide
How to measure a thrifted frame
Three measurements can describe the same frame. Here’s which one to use while you’re shopping.
1. Find the space the artwork sits in.
The usable opening is the space inside the frame where the artwork and backing fit. Measure its width and height from the back when the frame can be safely inspected. Don’t use the outside edges of the moulding.
If you can only see the front, the frame’s lip may hide part of the artwork. Treat that measurement as an estimate until you can check the usable opening. Ask the seller before opening or handling a fragile frame.
2. Separate the mat window from the frame opening.
A mat is the border between the artwork and the frame. Its visible window is usually smaller than the frame opening. A frame containing an 8 × 10 inch mat window may have a larger opening behind it.
Record the usable frame opening for matching. Save the visible window separately in your notes if you plan to keep the existing mat.
3. Save both sides and the units.
Write down width and height, for example 11 × 14 inches. In the app, select the units shown on your tape measure. Matching checks both orientations; you don’t have to rotate numbers in your head.
For gallery-wall planning, measure the outside of the complete frame as well. That is how much room it takes up on your wall.
4. Check more than size.
Inspect the glass, corners, backing, hanging hardware, and depth. An opening-size match does not tell you whether a thick canvas will fit, whether the materials suit delicate art, or whether the frame needs repairs.
For valuable or fragile artwork, ask a professional framer about mounting and materials before making changes.