US Letter vs A4: which frame fits which sheet

A4 is defined in ISO 216 and measures 210 x 297 mm (about 8.27 x 11.7 in) [1][4]. US Letter measures 8.5 x 11 in, which is 215.9 x 279.4 mm [3]. Kuhn lists Letter as 216 x 279 mm and states that ISO A4 is 6 mm less wide but 18 mm higher than the US Letter format [1].

Letter is commonly used as home or office stationery primarily in the United States, Canada and the Philippines [3]; Wikipedia describes its use across Latin America as variable [3].

A frame is sold for one sheet size, so state which sheet your artwork was built on when you ask for a frame.

In the ISO system the height-to-width ratio of all pages is the square root of two, about 1.414 [1]. Letter does not share that ratio. Kuhn gives the US basic sizes as 17 x 22 in (432 x 559 mm) and notes that the US format series has two alternating aspect ratios, 17/11 (1.545) and 22/17 (1.294) [1].

Kuhn adds that you cannot reduce or magnify from one US format to the next higher or lower without leaving an empty margin [1].

Say an overseas designer sends artwork built on a Letter canvas and you plan to frame it at A4. Kuhn gives the scaling factors: A4 documents have to be printed at 94% to fit the 6% less tall Letter paper, and Letter documents at 97% to fit the 3% less wide A4 format [1].

Between Borders adds a related point: a design that is centred on A4 can be a little off-centre on a US Letter page [2]. It also says that if such minor visual errors are unacceptable, there is little option but to prepare two versions of a design [2].

Treat the frame opening as a fixed rectangle and decide how artwork built for the other sheet size meets it.

Illustrative example. Letter artwork (215.9 x 279.4 mm [3]) scaled to 97% [1] becomes about 209.4 x 271.0 mm. That fits the 210 mm width of an A4 frame, but 297 minus 271.0 leaves about 26.0 mm of the height unfilled. The 209.4 and 271.0 figures are our own arithmetic, not from a source.

You have three choices.

• Match the sheet to the frame. Re-set the artwork on the native size of the frame before it is printed. This keeps the full design.
• Ask about a mount (mat). Ask your supplier whether a mount could cover a small mismatch at the edges, and how much overlap it needs, before ordering.
• Accept a crop or border. May be acceptable for a loose photographic image, but not for artwork with text close to the edge.

Three sizes are easy to confuse: the sheet size, the opening you see through the glass, and the outer frame size. Ask your supplier how much of the sheet edge the frame or mount covers, and state which of the three you mean in your brief.

Keep text and logos inside a margin from the trim edge so a small crop does not cut them off. Our artwork file checklist covers file preparation, and how to brief a frame or board order covers what to state in your brief.

1. State the sheet size in both units, for example "A4, 210 x 297 mm" [4] or "Letter, 8.5 x 11 in" [3] (see the table after the first section).
2. Say whether the opening size or the outer frame size is the one you mean.
3. If the artwork came from a Letter canvas and the frame is A4, or the reverse, say which dimension may be cropped or bordered.
4. Do not scale by eye; confirm any scaling factor on a proof.
5. For ranges sold in several markets, consider a separate artwork version for each sheet standard rather than one file scaled to both.

If you sell the same design across several marketplaces, our guide to own-label home decor for Amazon, Flipkart and Myntra covers how to plan sizes and sets.

ArtzFolio is a private-label manufacturer in Noida, serving businesses and brands only. Our quote confirms price, minimum order and lead time, and samples are paid, with the cost possibly reimbursed or adjusted by agreement. Payment is 50% advance, with the balance as agreed, and our shipping term is EXW Noida. Send your artwork size and sheet standard with your enquiry. See pricing, minimums and lead times or contact us. We reply within 1 business day.

1. International standard paper sizes, Markus Kuhn, University of Cambridge Computer Laboratory. cl.cam.ac.uk (read 2026-11-08)
2. A4 vs US Letter, Between Borders. betweenborders.com (read 2026-11-08)
3. Letter (paper size), Wikipedia. en.wikipedia.org (read 2026-11-08)
4. ISO 216, Wikipedia. en.wikipedia.org (read 2026-11-08)