Digital & everyday

Two-photo mat layout calculator

Plan one mat for two different-sized photos, side by side or stacked. Get window sizes, front-view coordinates and a scaled layout preview.

Your measurements

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Switch units without changing your quantities. The formula and worked example below keep their stated units.

in
in
in
in
in
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in
Mat board cut width
13.5 in
AB
Front view · A and B are the visible openings. Proportional preview; not a full-size cutting template.
Mat board cut height
9.25 in
Opening A width
3.75 in
Opening A height
5.75 in
Opening A left coordinate
1.5 in
Opening A top coordinate
1.5 in
Opening B width
5.75 in
Opening B height
3.75 in
Opening B left coordinate
6.25 in
Opening B top coordinate
2.5 in
Hidden paper-edge gap
0.75 in

Displayed values are rounded. Whole packages and purchase lengths round up. See assumptions below.

Calculation details

Inputs and full-precision results for checking this calculation. No report is sent.

How to use this calculator

Enter both complete print sizes and the overlap you want the mat to cover on every edge. Choose the layout and enter the gap between the visible windows. The smaller window is centered vertically for side-by-side photos or horizontally for stacked photos. A larger bottom border adds visual weight. Use the scaled preview to check the arrangement, then copy the dimensions and coordinates before planning the cuts.

The formula

Each window = photo dimension − 2 × overlap. Side by side: content width = window A width + gap + window B width; content height = the taller window. Stacked: content width = the wider window; content height = window A height + gap + window B height. Mat width = content width + 2 × side border. Mat height = content height + top + bottom borders. Center the smaller window on the shared cross-axis. Coordinates are measured from the mat’s front-view top-left corner.

A worked example

A 4 × 6 inch photo and a 6 × 4 inch photo, each overlapped by 0.125 inch per edge, need 3.75 × 5.75 and 5.75 × 3.75 inch openings. Side by side with a 1 inch opening gap, 1.5 inch side and top borders, and a 2 inch bottom border, the mat is 13.5 × 9.25 inches. Opening A starts at (1.5, 1.5); B starts at (6.25, 2.5), measured from the front-view top-left.

Assumptions & limitations

Exactly two rectangular prints, one mat layer and parallel edges; no rotation is applied automatically. The model uses physical print size, not pixel dimensions. It prevents hidden paper edges from overlapping or extending beyond the mat. Dimensions describe visible window geometry from the front, not the reverse-side cut lines or bevel-cutter stops. Mat board size is the insert size, not the frame’s outside dimensions. Check your cutter’s bevel and overcut instructions and your frame fit; dry-fit before cutting valuable board. The preview is proportional, not a full-size cutting template.

Common questions

Why does the gap differ from the distance between the paper edges?

The hidden part of each print extends by the overlap into the window gap. The physical paper-edge gap is opening gap minus twice the overlap.

Can I frame two unequal photos?

Yes. Enter separate width and height values for A and B. The smaller window is centered on the cross-axis, and the preview shows the result.

Is this a double mat calculator?

No. Two openings means two pictures in one mat layer. A double mat is two stacked layers and needs separate reveal and cut settings.

Supporting reference

The method above states this calculator’s assumptions. This reference provides related definitions and technical context.

Logan Graphic: planning and cutting multiple-opening mats ↗

Formula and worked example checked against automated test cases. About our methodology.

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