What size frame for artwork? This free picture frame calculator turns artwork dimensions and mat width into the exact frame size to buy. Enter your art, pick a mat, and get the frame size, picture frame glass size, visible mat opening, and outer footprint — plus a mat size calculator, a gallery wall spacing calculator, and a standard frame sizes chart.
How to calculate frame size in one step: the frame size calculator adds twice the mat width to each artwork dimension. That gives the nominal frame size to buy — the same number the glass shop needs for the picture frame glass size. Add the frame moulding width calculator field to see the full outer footprint on your wall.
This picture mat size calculator works two ways. Forward: enter artwork and mat width to get the mat opening size and the outer mat size. Reverse: enter a frame you already own to find what mat width it leaves around your art. The mat window overlap rule is built in — the opening is cut a quarter inch smaller per side so the mat holds the print.
Already own a frame? Enter its size to see what size mat for your photo it gives you.
Plan a gallery wall before you drill. List your finished frame sizes (outer dimensions, one per line), your wall width, and the gap you want between frames. The gallery wall layout planner returns the total run width, side margins, vertical placement, and a multi-row suggestion if the wall is too narrow.
Wondering what size frame for 8x10 print, what size frame for 11x14 print, or what size frame for 16x20 poster? Enter your artwork and desired mat width — the matcher checks the standard frame sizes chart and tells you which standard size fits, with a mat or without.
How to choose picture frame size starts with knowing what you can buy off the shelf. The most common standard picture frame sizes, verified against manufacturer and retailer lines, are below. Standard mat sizes for frames follow the same list — a 5×7 frame takes a 5×7 mat, and so on.
| Frame size (in) | CM | Mat / glass to order |
|---|---|---|
| 5 × 7 | 12.7 × 17.8 | 5×7 mat, 5×7 glass |
| 8 × 10 | 20.3 × 25.4 | 8×10 mat, 8×10 glass |
| 11 × 14 | 27.9 × 35.6 | 11×14 mat, 11×14 glass |
| 16 × 20 | 40.6 × 50.8 | 16×20 mat, 16×20 glass |
| 18 × 24 | 45.7 × 61 | 18×24 mat, 18×24 glass |
| 24 × 36 | 61 × 91.4 | 24×36 mat, 24×36 glass |
How to measure picture frame size correctly: measure the artwork edge to edge with a rigid ruler — width first, then height. That is the number every calculator on this page starts from. If the print has a border you want hidden, measure without it; if you want the border visible, include it and size the mat to cover the difference.
How to measure art for a frame with a mat: decide the mat width first (the picture frame mat width guide below), add twice that width to each artwork dimension, and buy the frame in that nominal size. A frame sold as a given size holds a mat cut to that same size — the nominal size already includes the mat.
How big should a mat be for a picture? The trade convention is 1.5 to 3 inches per side for most prints, wider for large pieces. The mat opening size calculator above cuts the window a quarter inch smaller per side than the artwork (mat window overlap), so the mat traps the print's edges. The mat width you enter here is the visible border between the window edge and the frame — the outer mat size is artwork plus twice that width per dimension.
Glass is cut to the outer mat dimensions — the same as the nominal frame size. The rule for how to measure glass for picture frame orders is a single number: the outer mat size. Measure the mat's outer width and height (or take the frame size you calculated above) and order the glass in that size. Glaziers and frame shops cut to the sixteenth, so give them the exact outer numbers from the frame sizer.
Every number below is computed by the same engine that powers the calculators above.
With a 2-inch mat, buy a 12×14 inch frame (30.5×35.6 cm). The picture frame glass size is the same 12×14 inches, and the visible window is 7.5×9.5 inches (19.1×24.1 cm) because the mat overlaps the print a quarter inch per side. With no mat, an 8×10 frame fits exactly.
Add twice the mat width to each artwork dimension: frame width = art width + 2 × mat, frame height = art height + 2 × mat. A 16×20 print with a 3-inch mat needs a 22×26 frame, with a visible window of 15.5×19.5 inches. The frame moulding width calculator field then adds the moulding face: with a 1.5-inch moulding the outer footprint is 25×29 inches.
The trade convention is 1.5 to 3 inches of mat per side for most prints. Run it through the mat size calculator: an 8×10 photo with a 2-inch mat gives a 7.5×9.5 inch window and a 12×14 inch outer mat – so you buy a 12×14 frame.
Cut the mat window a quarter inch smaller per side than the artwork, so the window is the artwork minus half an inch each way and the mat traps the print's edges. A 10×14 print gets a 9.5×13.5 inch window. Covering less than an eighth of an inch risks the print slipping out.
An 8×10 photo in an 11×14 frame leaves 1.5-inch side mats and 2-inch top and bottom mats – off-ratio, so the borders are uneven. For an even 2-inch mat all around, use a 12×14 frame instead.
The short answer to how far apart to hang pictures: 2 to 3 inches between frames, with most designers landing on 2. The gallery wall spacing calculator above shows why the math matters: three frames (16×20, 11×14, 8×10) at a 2.5-inch gap span 40 inches, leaving 40-inch margins on a 120-inch wall, with the visual center at 57 inches high.
Order the glass in the outer mat size – the same as the nominal frame size. For the 8×10 print with a 2-inch mat above, the picture frame glass size is 12×14 inches (30.5×35.6 cm). Give the glass shop the exact outer numbers; they cut to the sixteenth.
The most common standard picture frame sizes are 5×7, 8×10, 11×14, 16×20, 18×24, 24×36 inches, verified against manufacturer and retailer lines. Standard mat sizes for frames follow the same list. Anything outside it – or an artwork-plus-mat combination that lands between sizes – needs a custom frame.
Without a mat, an 11×14 frame is the exact fit. With a 2-inch mat you need 15×18 inches, and the smallest standard size that fits is 16×20. That is the standard size matcher logic: it checks every size on the standard frame sizes chart, rotation included.
Yes – the nominal frame size IS the outer mat size. An 8×10 artwork with a 2-inch mat takes a 12×14 frame, not an 8×10. The moulding itself sits outside that number: with a 1-inch moulding face the finished piece measures 14×16 inches on the wall.