The A Paper System - Paper Size Table and Information on A3+

The ISO/DIN standard A paper system is an elegantly designed system for classifying paper sizes where each size is half that of the last, starting from the A0 master sheet size.  Alternatively you can look as it as each sheet doubling in size as you go up each size, so A4 is double A5, A3 is in turn double A4 and so on.

The fact these sizes are standardised brings many advantages to working at these sizes in your fine art / giclee printing - for example, you can often use inexpensive standard sized frames for your work if you stick to these sizes.  And indeed, if you're an artist, then drawing or painting at these sizes (ideally leaving a little whitespace border) makes getting your work scanned in a generally cheaper and easier process.  Thus we recommend that wherever it reasonably suits your art practise, you try and fit your work within the A system.

The most common sizes of relevance to fine art / giclee printing are listed in the table below.

The A System Paper Size Table

How Does A3+ Fit In?

 (A3+ is also called sometimes called Super B)

This is perhaps best looked at visually.  The most common fine art print sizes are A4, A3 and A2.  However, if you line these sizes up visually on a wall, there is a sense of a missing step between A3 and A2 - that particular doubling in size seems much more than a single size step.

A3+ is a non official size that effectively allows a more sensible stepping of sizes along this system. 

It was, it seems, originally made common as a size so that you could print full bleed A3s out on printers that couldn't do borderless printing, and the result is that for years now office model printers are never really A3 printers, but in fact they are all A3+ printers (that is, their carriage width is increased from the 297mm needed for A3 to the 329mm needed for A3+ so that you can print out a full size A3 on the A3+ sheet and cut it down to a full bleed A3).

Now, modern printers tend to offer borderless printing modes anyway, so that historical use of A3+ is largely in the past....but A3+ does now provide a very handy extra size along the typical size scale for fine art prints.

Another odd thing about A3+ is that paper in that size is often as cheap, or cheaper, to purchase than the A3 size of the same type - which seems ridiculous as the sheet size is bigger!  Well, this is an aberration that results from how the papers are made - in a nutshell, they can cut A3+ sheets from the 'mother roll' more cost effectively than they can cut A3 sheets, so despite the bigger sheet size, it can actually be cheaper to produce A3+ than A3 - through less wastage!

There is technically also an A4+ size out there, but we've not seen any inkjet stocks available in that size, so we've left it out here.

The More Complete A Paper Size Table, including A3+

This is cool....

If you need any more info on paper sizes then PaperSizes.io is great!

And reader Bernard contributes another cool fact about the A system paper:

• The area of an Ax sheet is 1 divided by 2 to the power of the paper size, x. 
• So A0 paper is 1 square metre (2 to the power zero is 1) and an A4 sheet is 1/16th of a square metre