Frame & Mat Size Calculator
Work out every dimension of a matted frame from one measurement of your art — the window opening, the glass and mat-board size, and the finished frame — before you order or cut anything.
Measure once, order the right size
The confusing part of framing is that no two of the sizes match: the art, the window, the mat board, and the frame are all different, and mixing them up means glass that doesn't fit or a mat that swallows the picture. Enter the art and the border once and the tool untangles the stack for you, so the glass, backing, and frame all agree.
With the frame size in hand, size it to the furniture below using the Frame Size for Wall Calculator, or place it in a row with the Gallery Wall Spacing Calculator.
Frequently Asked Questions
What size frame do I need for a matted print?
A matted frame stacks three sizes. The mat cuts a window a little smaller than the art so it overlaps the edges; the outer mat board adds the border you choose on every side, and that mat-board size is what the glass, backing, and frame rabbet must match. Enter your art size and mat border and the tool returns all three, so you can buy a ready-made frame in the mat-board size or cut one to fit.
Why is the mat window smaller than the art?
The mat has to overlap the edges of the art by a small amount — a quarter inch per side is standard — so the print can't slip through the opening and so no white border shows. That means the visible window is the art width minus twice the overlap. The tool defaults to a quarter-inch overlap but lets you change it if your print has a border you want to hide or reveal.
How wide should the mat border be?
Two to three inches suits most prints, and a wider mat — three to four inches or more — gives a small piece a gallery presence and draws the eye inward. The border is the visible mat on each side, from the window edge to the mat-board edge, and the tool applies it evenly all around. For a classic look some framers weight the bottom border slightly heavier, which you can approximate by nudging the size after.
Does this include the frame molding?
Yes, optionally. The mat-board size is the glass and rabbet size — what most ready-made frames are sold as. If you enter a molding face width, the tool adds it on every side to give the finished outer edge of the frame, which is what you measure against the wall and use for spacing. Leave the molding at zero to get just the glass and mat-board dimensions.
Estimates for planning only. Confirm exact sizes with your framer or the ready-made frame's stated dimensions before cutting or ordering glass.