How to Frame a 21 × 21 cm Art Print (When Square Is Not a Standard Size)

My hand-signed prints are 21 by 21 centimeters, which is a lovely size to look at and a slightly annoying size to buy a frame for. Square is not a standard frame format, and 21 centimeters is not a standard anything.

I get asked about this often enough that it deserves its own page. Here is what actually works, from the five minute version to the one I would do myself.

First, what you are framing

A print from my shop is a 21 by 21 centimeter sheet with the artwork printed inside a white border. That border is part of the piece rather than packaging. On the front, in the border, sit my initials and the blind embossed stamp. On the back there is a handwritten dedication and a second stamp.

Two things follow from that. Do not trim the paper down to the image, and do not cover the bottom border with a mat without checking where the initials and the embossing actually sit on your copy.

Option 1: a 25 by 25 frame and a sheet of colored card

This is the cheapest good answer and the one most people end up happy with. A 25 by 25 centimeter frame is a normal shop item, IKEA sells one in the SANNAHED range, and plenty of other brands make the size.

Cut a piece of card to 25 by 25, center the print on it, and you get an even two centimeter border of color around the sheet. White or cream looks classic. Black makes the colors pop. A pink or turquoise card picked out of the artwork looks deliberate and costs nothing extra, which is very much my kind of solution.

Fix the print with acid free photo corners or paper hinges rather than glue or normal tape, so it can always come off again.

Option 2: a 30 by 30 frame, with or without a mat

A 30 by 30 centimeter frame is even easier to find and gives the print a generous four and a half centimeters of space on every side. That extra air makes a small print look like a serious one, which is exactly why galleries do it.

You then have two ways to go:

• Mat on top. A passepartout with a window slightly smaller than the sheet, around 20 by 20 centimeters, sits over the edges and hides roughly five millimeters of paper all round. Clean and traditional. Check first that it does not swallow the initials or the embossing.
• Float mount. The sheet sits on top of a backing board with a visible gap all around, so the entire print stays visible, borders, signature, embossing and all. This is what I would choose, because the embossed stamp is part of what you paid for.

Option 3: a frame made to size

A framer will happily make you a 21 by 21 frame, and for a piece you love it is worth it. It costs noticeably more than anything off a shelf, so it makes the most sense once you own a few prints and want them to match. Ask for acid free backing and, if the wall gets daylight, glazing with UV protection.

If you like secondhand hunting, the older IKEA RIBBA square in 23 by 23 centimeters still turns up on classified sites, and a 21 centimeter sheet sits nicely inside it.

Option 4: no frame at all

Not everything needs glass, and if you rent, this is often the better answer:

• Magnetic wooden poster hangers. Two wooden strips that clamp top and bottom, hung from a cord. Cheap, quick, and they suit a square sheet surprisingly well.
• Bulldog clips on a wire. A whole row of prints, swappable in seconds. Very good if you like changing things often.
• Washi tape. Yes, really. It holds fine, it comes off the wall, and it costs nothing. Use it on the border, never across the artwork.

The rules that matter whatever you choose

• Give the embossing some light. A blind embossed stamp is only visible when light hits it from the side. A mat or a float mount keeps a little space between glass and paper, which is what lets the relief throw its small shadow.
• Acid free everything. Backing board, mat, corners, tape. Cheap cardboard yellows the paper over the years, and it starts at the edges where you will notice it.
• Keep it out of direct sun. No glass saves a print that hangs in an afternoon sunbeam. UV glazing helps, moving the piece helps more.
• Never trim the sheet. The border, the signature and the embossing are what make it a signed print rather than a poster.
• Hang it at eye height. Middle of the picture at roughly 145 to 150 centimeters. Most people hang art too high, including me, until I measured.

Several square prints on one wall

Square prints are unusually easy to group, because identical formats do the tidying up for you. Same frame color, same spacing, and it reads as one thing rather than several.

• Keep the gap between frames consistent, five to seven centimeters works for this size.
• A grid of four or nine 25 by 25 frames looks intentional. Three in a row works on a narrow wall.
• Mixing sizes is fine as long as the frames match. Let the artwork be the loud part.

There is a whole guide to that in How to Build a Pastel Goth Gallery Wall.

If you would rather skip the maths

The hand-signed prints are all 21 by 21 centimeters, signed by hand and embossed, for 35 euro. They are the ones this whole article is about.

If you want something that drops straight into a frame you already own, the poster versions come in square inch sizes from 10 by 10 up to 24 by 24 inches. Worth knowing in Europe: ten inches is 25.4 centimeters, so an inch size sits slightly proud of the nearest centimeter frame. Either buy the frame in inches, or trim a few millimeters off the edge, which is fine on a poster and never on a signed print.

And the printable versions let you print at whatever size your frame happens to be, which is the most practical answer of all if you have one empty frame and a very specific gap on the wall.