Illustrator Bleed

When setting up new documents within Adobe Illustrator one of the parameters we have to consider is that of the bleed amount. As we shall see the issue of bleed is only really relevant when working with print media; the issue is not a factor when creating online documents.

The term bleed is used within the printing industry to indicate the "safe" area outside the trim edge, or paper edge, of document. This will ensure that our artwork will be printed to the edge of the paper, vinyl or card. Printing companies vary as to how much bleed they require, but many will specify between 2mm and 5mm bleed. This is the average range of bleed required in small and mid-range documents, ie. business cards, or DL (which stands for Dimension Lengthwise, an envelope size) or A4 and A5 type flyers.

But for larger printed posters and banners the printing company will often ask for a 10mm bleed. In then end we should always first check with our printing company before sending our finished artwork to print.

The question often asked is why is bleed is required in the first place? Many documents such as flyers and posters will be printed with 8 or 16 to a sheet. These sheets are then trimmed using double-edged high-speed trimmers. The problem is that these trimmers are not 100% accurate, so that when the artwork is set up only to the edge of the document (ie. the black trim edge), we could have small thin white strips at the edges of the print job. If we scale the artwork up to the red bleed guide (eg.3mm), we ensure that the design will be printed to the paper (trim) edge.

We usually specify the bleed amount in Illustrator's New Document dialog box. If we forget, however, or if we need to adjust the bleed amount later, on we can do this via the File drop-down menu, and choose Document Setup.

To see the bleed guide in action, we then create our PDF in order to send to our commercial printer. Go to the File menu and select Save As or Export. On the left hand side we see a large panel with various options. We open the section marked Marks & Bleeds and select the check boxes marked All Printer's Marks and Use Document Bleed Settings. Here we can see the bleed amount we specified at the initial setup of the document.

Related to bleed guides are the margins - these are simply guides to ensure that items like text and graphics are not printed too close to the trim edge. This is an aesthetic issue rather than a technical print matter. For an mid-range size document a good rule of thumb is about 12-15mm, whereas for a large poster or banner margins can range from 50-100mm. Again, it's best to consult your commercial print provider, or consult their website before setting up the job.

When we attend to details like bleed and margins, we will ensure that we have complete control over the printed results and our artwork will be printed to a professional standard.


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Tom Gillan has been training illustrator to corporate clients in Sydney for seven years. If you like to know more about illustrator, visit http://www.designworkshopsydney.com.au/adobe-illustrator-courses/ for more information.