Is 20 x 24 a Standard Frame Size? | Yes, Here’s How It’s Used

Yes, 20 x 24 is a standard U.S. picture frame size, commonly used for large prints and matted 16 x 20 artwork.

The 20 x 24 measurement appears on standard size charts across the framing industry, alongside 8 x 10, 11 x 14, and 16 x 20. It’s stocked by most major retailers and custom framers, has a 5:6 aspect ratio suitable for photography and art prints, and is easy to buy off the shelf.

What trips people up is not whether 20 x 24 is standard, but what that label refers to: the frame’s outside dimensions, the artwork size it holds, or the mat opening inside. Knowing which one you’re looking at matters far more than the label itself.

Why 20 x 24 Is Considered A Standard Size

Standardization means a size is common enough that retailers stock it and manufacturers produce it in volume. Austin Gallery’s standard picture frame size guide lists 20 x 24 among conventional U.S. sizes. This status brings practical benefits: more ready-made frame options, more mat combinations, and more consistent pricing than a one-off custom size—letting you walk out with a frame that day rather than waiting weeks.

What Fits Inside A 20 x 24 Frame

A 20 x 24 frame holds either a 20 x 24 print with no mat, or a smaller image when you add matting. The most common pairing is a 16 x 20 print with a mat. When framing a 16 x 20 image, the mat needs an opening of roughly 17.75 x 19.75 inches—smaller than the print itself, which is correct, as the mat overlaps the artwork’s edges to hold it in place. This is the source of most framing confusion: the mat opening is not the print size, and neither equals the frame’s outside dimensions.

• Frame size label: 20 x 24 inches, the outside measurement of the frame
• Mat opening: Around 17.75 x 19.75 inches, sized to hold a 16 x 20 print securely
• Artwork: 16 x 20 inches, the actual photo or art print you’re displaying

If you’re framing a 20 x 24 print, no mat is needed—the print fills the frame edge to edge. For a 16 x 20, the mat must be cut to the correct opening. Don’t buy a mat based on the frame label alone; check the opening measurement before ordering.

How Framers And Retailers Label The Size

Framing industry sources treat 20 x 24 as standard, but labeling isn’t uniform. Some shops describe the frame by the artwork size it’s designed to hold, while others list the outside dimensions. A frame listed as “20 x 24” at one retailer might hold a 20 x 24 print, while at another it might refer to the exterior measurement, making the viewing area smaller. Always check the product description for the exact inside measurement or stated artwork size before purchasing.

“Standard” also doesn’t mean universal. Retailers and custom framers may vary in labeling and precise dimensions. Standard means commonly available, not that every framer treats it identically.

When 20 x 24 Is The Right Choice

Choose a 20 x 24 frame for a 20 x 24 print without a mat, or to frame a 16 x 20 image with generous matting. The 5:6 aspect ratio suits portraits, landscape photography, and standard art prints. For a 16 x 20 print, the frame gives room for a border that visually anchors the artwork. If you’re ready to compare options, our tested roundup of the best 20 x 24 frames walks through top picks for both use cases.

When shopping, measure your artwork first, then work backward to the frame. Knowing whether you need a mat, and the correct mat opening, turns a confusing purchase into a quick one.