# A1 size paper: minimum font size

What is really the smallest possible font size I can use for A1 poster which is not going to be viewed from a great distance (its a genealogy diagram, mostly for studying from up close).

I need to fit some portraits and additional information, but also retain at least a bit of reading comfort.

A1 is a beast, so I think it could be even a quite small font size (like 12-11?) - but I dont want any ill surprise during the printing process, hence my question.

• Commented Jun 15, 2020 at 12:54
• The maximum readable size of a font does not depend on the paper size. It will depend on how close the viewer is to the poster, and how good their eyesight is. Commented Jun 15, 2020 at 21:01

12 point text on A1 paper is the same size as 12 point text on A4 (or Letter)

Try holding up a printed sample and see at what distance you can read it. Then imagine the same A4 paper tiled in a 2x4 matrix - do you need to see/read all the corners at once?

That should give you a practical example of how big it will be and how readable the fonts are at that distance.

• Are you sure it should be 4x4 matrix? A3 would ba `2x1 A4`, then A2 would be `1x2 A3` so `2x2 A4`, then A1 will be `2x1 A2` so `2x2 A3` so `4x2 A4`. I think, it's confusing when I write it like that. Commented Jun 16, 2020 at 8:47
• @Maurycy dang, you're right. I had to draw it out to be sure. Commented Jun 16, 2020 at 12:46

Is not going to be viewed from a great distance

Reading a text on a post-it, or reading the same size text from a poster does not depend on the size of the paper, it depends on the viewing distance and the size of the text.

There are some other factors like the font design, but let's think that you are using a simple sans serif font like arial.

I don't want any ill surprise during the printing process

1. Define what is the "printing process".

The only way to avoid any "surprise" is actually using that printing process before.

Go and ask for a print sample similar to what you need to print. In fact, send a small size sample, for example, a small strip of 30 cm linear (they print a roll, so your sample should be the same size of the roll x the length of the file.

But probably the other surprises will come from your design process, for example, if you are not working with vector files.

A1 is a beast, so I think it could be even a quite small font size (like 12-11?)

It seems that you are thinking of some kind of re escalating. Am I right?

If you work at a scale, you need to think all at scale. If you want a final size of A1, you could make a design on an A3 artboard which will be at 50% scale.

Working with an A4 artboard will be confusing because the scale is 35.35%

In short. Define the viewing distance, print a sample text on your home printer and paste it on the wall. Take notes.

Define your scale. 50% is a good, easy to work scale.

Send the file in vectors. Print a small sample using the same process as the final files.

Take a look at this similar questions.

What line width is appropriate for a scientific A0 poster?

Artwork size - downsampling

12 pt should not be an issue for printing, also it should be relatively easy to read from "up close".

However, A1 is quite a large format, so I think it is best to experiment a bit with possibly larger font sizes, assuming the artwork does not need to be super crammed.

Use a normal A4 printer, put some 12, 14, 16, 18 pt type on it, print at real size 1:1, stick it on the wall, and try to read it from "up close".

Then, with this in mind, visualize how to adjust your content to possibly work with a larger font size, maybe 14, 16, 18 pt, etc.

The font size you choose does not necessarily correlate to the size of the medium you are producing. As you have mentioned in your question, the context in which the information will be read is far more important.

As the readability of a font depends on many different factors such as x-height, serif/non-serif, line spacing, it is hard to give general advice on sizing.

What works best for me, is to print samples of your text different type sizes on A4 and tape them to the wall. Then check the readability from different distances.

The paper size is irrelevant to print quality. The question you should be asking is is your font readable at a given resolution, more commonly referred to as DPI (Dots per Inch).

I've printed plans on A1 and A0 with 8pt fonts so 12pt should be no issue. However the DPI of the printer is what determines how small you can print. I don't have multiple printers with different DPI capabilities so let me illustrate the issue by drawing 8pt text in various Photoshop files at various resolutions.

The following are example close-ups of 8pt text at various DPI:

As you can see, the DPI of the output will affect how the printed text looks on paper. The actual output may not be pixelated like the image above but will be similarly blurry.

For reference, 300 DPI is roughly the resolution of comic books. Newspapers print at roughly 160 DPI and magazines print at 600 DPI. If you're printing digitally most print shops these days use large format printers capable of 2400 DPI.

If you're mass producing your poster and send your artwork to a commercial/industrial printer then you may hear another specification for resolution: LPI or Lines per Inch. The standard conversion from DPI to LPI is 2:1 so 300 DPI is 150 LPI. Just multiply LPI by 2 to get DPI or divide DPI by 2 to get LPI. So magazine quality is roughly 300 LPI.

Since you're intending to use 12pt text which is much larger than 8pt you don't have much to worry about since most print shops will print at much higher resolution than 300 DPI these days.

However, do note that the DPI applies not only to the printer capabilities but also the resolution of your artwork. If your artwork is in a vector format such as SVG or Adobe Illustrator then it basically has infinite resolution and you don't need to worry about it. But if you are working in Photoshop of are generating a TIFF or JPG file then all the above applies to your file as well.

For reference, a bitmap (JPG, PNG etc) file with A1 size at 300 DPI is 7016x9920 pixels (a bit larger than 8k TV resolution).

The following are example close-ups of 12pt text at different resolutions:

Now you know how to generate the correct artwork to print on A1 correctly and what question to ask your printer.

• While I understand the point you are trying to make, showing examples of pixelated type may be more confusing than helpful here; especially as resolution is - as you state yourself - a rather minor issue regarding this question.
– dom
Commented Jun 16, 2020 at 8:21
• @dom It's only minor until someone tries to print a 1080x1920 image on A1 which is why I show how the text looks at different resolution. One needs to make sure that both the file and the printer can handle the resolution one wants. If you already understand this then it's not necessary. But it's hard to describe it in just words so pictures help a lot Commented Jun 16, 2020 at 9:02