You may have heard your designer talk about your document needing ‘bleed’ or you may have had a printer ask if your document has ‘bleed’, but what is it?
When you have any printed document, whether it is a flyer, a brochure, a magazine or a catalogue, the paper size it was printed on will be bigger than the finished item you hold in your hand. Depending on the job it may have been printed on a sheet that is just a few centimetres wider and taller, or it could have been printed with lots of other flyers (or pages from your document) on an enormous sheet, or even on a continuous roll of paper.
What this means is that at some point the printed sheets need to be cut down to the finished size, and this is why bleed is important. For anything that ends at the edge of the page, whether it is an image, graphics or anything else, it is important that these elements ‘bleed’ over the edge of the page rather than end at it. Why? Well, because when print jobs are guillotined down to size they may be cutting hundreds of pages at once and any slight movement in the page will mean that the cut edge may move ever so slightly. If your image only extends to the end of the page then you may end up with a thin white line, which looks bad.
Modern equipment generally means that movement when ‘trimming’ pages is minimised, but it still makes sense to add bleed to all print documents just to be safe. That way if there is a slight inaccuracy in the way the page is trimmed it will not be noticeable.
How do I apply bleed, and by how much?
In modern Desktop-publishing software (DTP) the document you create can be set up with a ‘trim’ size, which is the final size of the page and a ‘bleed’ amount which extends beyond the page boundary, but which can be hidden when previewing the final design. The software will generally allow you to automatically add ‘trim’ marks to the document to confirm where the edges of the page are and where the bleed starts.
If this is not available in the software you are using then the best option is to make the page to the ‘bleed’ dimensions so that when you provide it to the printer it is accounted for – in this case, though it is wise to use guidelines (if available) to indicate where the true edges of the document actually are, so you can see what will be left when it is trimmed. It’s not ideal as there will be no ‘trim’ marks to confirm where the bleed starts, but it is better than no bleed at all.
What if I don’t add bleed?
If your printer is provided with a document with no bleed they have two options:
Keep the size – and run the risk of getting a white edge or two
‘Blow up’ the document – so that it fits the ‘bleed’ dimensions, but then all your content will be much closer to each of the edges, which will affect the balance of the design
How much bleed should I add?
The industry standard is 3mm on each edge, i.e you increase the document’s total width and height by 6mm, but it can vary from this for certain projects so it is always best to ask the printer.
Click the images below to see a comparison of the same document before it is trimmed (i.e with bleed) and after it is trimmed. Hopefully, these images along with the description above help explain the principle, but if you are still unsure please contact us we’d be happy to talk you through it. You might also find our glossary useful for this and other technical terms.