Signs & Large Format Print
Where A sizes come from
The whole system rests on one clever ratio: the long side is √2 times the short side (about 1.414). So when you cut a sheet in half across its long side, you get two smaller sheets with exactly the same proportions. A4 gives two A5s, A3 gives two A4s.
The starting point is A0, with an area of 1 m². Hence a simple rule: A1 is half a square metre, A2 a quarter, A4 is 1/16 m². In a print shop this makes calculations much easier – we know straight away how many items fit on a sheet and how to convert a price per m² into a price per piece.
The standard applies in Europe and most of the world. The exceptions are the USA and Canada, which use Letter (216 × 279 mm) and Legal (216 × 356 mm). If a file comes from a client across the Atlantic, we always check whether it is in Letter – once scaled to A4, the margins go out of line.
A0–A8 sizes in mm and in pixels
| Size | Dimensions in mm | Pixels at 300 dpi | Typical use |
|---|---|---|---|
| A0 | 841 × 1189 | 9933 × 14043 | Exhibition posters, plans, technical drawings |
| A1 | 594 × 841 | 7016 × 9933 | Posters, display boards, A-board posters |
| A2 | 420 × 594 | 4961 × 7016 | Posters in shop windows and on notice boards |
| A3 | 297 × 420 | 3508 × 4961 | Small posters, menus, price lists, drawings |
| A4 | 210 × 297 | 2480 × 3508 | Letterheads, flyers, proposals, catalogues |
| A5 | 148 × 210 | 1748 × 2480 | Flyers, brochures, notepads, invitations |
| A6 | 105 × 148 | 1240 × 1748 | Flyers, postcards, vouchers |
| A7 | 74 × 105 | 874 × 1240 | Tickets, discount cards, small flyers |
| A8 | 52 × 74 | 614 × 874 | Labels, tags, tickets |
300 dpi is the resolution we need for print viewed up close – a flyer, a catalogue, an indoor poster. For large formats viewed from several metres away, less is enough; we explain this in what resolution for large format printing. The dimensions in the table are trimmed sizes, i.e. after cutting.
B and C sizes: posters and envelopes
The B series fills the gaps between A sizes. B1 sits between A0 and A1, B2 between A1 and A2, and so on. You will most often come across:
- B1 – 707 × 1000 mm, the classic film and concert poster size,
- B2 – 500 × 707 mm, posters in schools, public offices and on advertising columns,
- B3 – 353 × 500 mm, smaller posters and wall calendars,
- B5 – 176 × 250 mm, exercise books, books, some catalogues.
The C series was designed for envelopes. A C4 envelope (229 × 324 mm) holds a flat A4 sheet, C5 (162 × 229 mm) an A4 folded in half or an A5, and C6 (114 × 162 mm) an A4 folded twice. Then there is the popular DL envelope (110 × 220 mm) for an A4 folded in three.
If you order printed envelopes together with letterheads, choose the envelope size right away to match how the letter will be folded.
Special sizes: DL, square, billboard
Not everything we print fits the ISO standard. A few non-standard sizes come up very often:
- DL (99 × 210 mm) – a flyer one third of A4 wide. It fits a DL envelope, sits well in leaflet racks and in the hand. A DL leaflet is made from an A4 folded in three.
- Square (e.g. 148 × 148 mm, 210 × 210 mm) – invitations, product catalogues, booklets. It stands out from the standard, but leaves more waste on the sheet, so it can cost a little more.
- Business card – in Poland and most of Europe 90 × 50 mm or 85 × 55 mm.
- Billboard sizes – measured in metres, not in A or B series. In Poland the standard billboard is 504 × 238 cm, and 6 × 3 m boards are also common; in other countries sizes vary, so we always ask for the dimensions of the specific board.
For citylight frames and billboard posters, the frame size counts, not the standard size – see the citylight and blueback posters page.
- 24 hexpress printing (UV inks need no drying)
- approx. 3 daysstandard lead time
- up to 14 dayslarge and custom projects with installation
Plus courier delivery. Tell us your date — we plan production around it.
Trimmed size, bleed size and bleed
This is the most common source of misunderstandings with files. The trimmed size is the size of the finished product after cutting, e.g. A4 = 210 × 297 mm. The bleed size is the trimmed size plus bleed – usually 2–3 mm on each side for small formats. So an A4 flyer file with 3 mm bleed measures 216 × 303 mm.
Why? A guillotine cuts with a small tolerance. If the background ends exactly at the edge of the page, a thin white line of paper may remain after cutting. Bleed is extra artwork that gets trimmed off. Text and logos, on the other hand, should stay a few millimetres in from the edge – in the so-called safe area.
In short:
- Set the document to the trimmed size (e.g. 210 × 297 mm).
- Add 3 mm bleed (for flyers and posters) and extend the background to the bleed edge.
- Keep important content at least 3–5 mm from the trim line.
- Export a PDF with bleed.
More details and examples are in what is print bleed.
Which size for what
A few practical tips we give clients at the counter:
- Flyer to hand out – A6 or DL. A5 for a larger offer. More on choosing in which flyer size to choose.
- Shop window poster – A2 or B2; for a notice board in a residential block – A3 or A4.
- Event or film poster – B1 or A1.
- Letterhead, proposals – A4, with a DL or C4 envelope.
- Catalogue – A4 or A5, possibly square; with saddle stitching the page count must always be divisible by 4.
Indicative prices from our price list, net: A2 posters on 170 g silk – approx. €28 for 10 pcs and approx. €85 for 100 pcs; A4 letterhead – approx. €49 for 500 pcs; 6-page DL leaflet – approx. €90 for 1,000 pcs. Prices are indicative and we confirm them once you contact us; non-standard sizes are quoted from a short description.