A0 to A6: A Quick Guide to Paper Sizes and When to Use Each
Exact dimensions for every common A size, with a note on what each one is actually useful for.
From the team at The Printing Shop.
The A series has a neat trick: each size is exactly half the previous one. Fold an A1 sheet in half and you have A2. This means artwork scales between sizes without any of it being cut off or stretched, which is why the system is used across most of the world.
A series dimensions
| Size | Millimetres | Inches (approx.) | Common uses |
|---|---|---|---|
| A0 | 841 x 1189 | 33.1 x 46.8 | Large posters, plans, academic conference posters |
| A1 | 594 x 841 | 23.4 x 33.1 | Posters, A-board inserts, welcome signs |
| A2 | 420 x 594 | 16.5 x 23.4 | Shop window posters and noticeboards |
| A3 | 297 x 420 | 11.7 x 16.5 | Folded menus, small posters and charts |
| A4 | 210 x 297 | 8.3 x 11.7 | Letterheads, reports and documents |
| A5 | 148 x 210 | 5.8 x 8.3 | Flyers, booklets, orders of service |
| A6 | 105 x 148 | 4.1 x 5.8 | Postcards, small flyers and invitations |
| A7 | 74 x 105 | 2.9 x 4.1 | Small tickets and handouts |
Why the shape stays the same
All A sizes share the same proportions, with the long side about 1.414 times the short side. An A0 sheet has an area of exactly one square metre, and each smaller size is half of that. This is why you can enlarge an A4 to A3 on a copier without any white bars. It is also the reason that eight A4 sheets make up an A1, and sixteen make up an A0.
How to scale artwork
Going up one size means multiplying each side by about 1.41, or 141% on a photocopier. Going down one size means reducing to about 71%. If you scale a file, remember that small text gets smaller too, and images get less sharp as they get bigger. Check them at the final size.
Other sizes you may come across
- DL (99 x 210 mm) is a third of an A4 sheet. It is very common for leaflets, compliment slips and invitations, and it fits a standard DL envelope.
- Business cards (85 x 55 mm) are a standard size across the UK.
- C-series envelopes are slightly larger than the A-series. A C5 envelope fits an A5 sheet, and a C4 fits A4. See printed envelopes.
- US Letter (216 x 279 mm) is slightly wider and shorter than A4, and it can cause problems when printing documents from US templates.
Which should you choose?
Start from where the print will be used. Measure the frame, noticeboard or display rack, then think about how far away people will be standing. Text needs to be much larger on a poster read from three metres than on a flyer held in the hand. If you are not sure, tape sheets of A4 together on the wall to see what size looks best.