InDesign Basics: What is a Bleed and When Do I Use It?
If you’re preparing any document for professional printing, it’s a given that you’ll need to allow for a Bleed in your InDesign document. In this quick tutorial we’ll give some answers to these commonly asked questions:
What the heck is a Bleed??
When do I need to use a Bleed?
How do I add a Bleed to my InDesign document?
How do I export my document, including the Bleed?
1. So…what exactly is a Bleed?
This is a really common question, so don’t worry if you don’t know (or think you know, but aren’t completely sure!).
A Bleed is the area just extending past the edge of the page, past the trim edge. So here in this diagram you can see the edge of the bleed marked out skirting around the outer edge of the page.
A Bleed acts as a margin of error when the document is trimmed, after it’s been printed. So, if you have any content that will cross the edge of the page, such as a coloured background or maybe an image, you should extend it into the bleed to avoid any white lines appearing around the edge of your document. Printers are human after all – trimming errors can happen, and they are just an inevitable part of the print process. This could just be a tiny millimetre-wide margin of error, but if you don’t extend your content into a bleed, it will still be visible.
By including a bleed in your InDesign documents you can help to make your final print product look flawless, and minimise the visibility of any trimming errors.
2. When do I need to use a Bleed?
A Bleed is essential to include if you’re creating any document for print. The rule for applying a bleed in InDesign is as follows:
If you’re creating a single page document you can set a bleed all the way around the document.
But if you’re creating a document with facing pages, that’s going to be bound, like a book, you don’t need to include a bleed on the inside edge. Firstly, because nobody’s going to see it, as the page edge will be sucked into the bind, and second, because if you export the InDesign document as a spread (not as single pages), the bleeds on the inside edges (the inside is the edge of the page that will be bound) will cross onto the opposite page, which is unsightly, like in the example below.
This magazine spread was mistakenly set up with a 5 mm bleed on the Inside Edge, but on exporting the spread as a PDF, it becomes apparent that the content of the inside bleed has spilled onto each opposing page. You can see that the image of the fish has crossed the central page divider, and spilled into the image of the boats.
If you’re creating a document made up of facing pages, that you’re intending to bind, be sure to set the bleed on the Top, Bottom and Outside edges only. We’ll take a look at how you can set up your bleed in InDesign next.
3. Add a Bleed to your InDesign document
It’s best to set up your InDesign document with a bleed before you start working on your document. You can add a bleed later, by going to File > Document Setup, but it can be fiddly as InDesign will only apply your revised settings to the pages you currently have selected.
The best place to start is right at the beginning of the process, in the New Document window. When you go to File > New > Document to create a new InDesign document (or select New > Document from the Welcome window), the option to apply a bleed to your document is down at the bottom of the New Document window, just above Slug.
In this example, I want to create the inside pages for a paperback book. Because the pages are going to be bound in the center of each spread, I won’t need a bleed on the Inside edge.
I type in 3 mm into the Top Bleed text box, then click the chain icon at the far right of the Outside text box to break the uniform values, and get rid of the bleed on the Inside edge, reducing it to 0 mm. Once I’ve set up the rest of my document I can close the panel and create the new document by clicking OK.
4. Export your InDesign document with a Bleed
Once you’ve finished your InDesign artwork and are ready to export it to a print-ready format, you should ensure that your beautiful bleed is exported along with the rest of the document.
The best way to prepare a print-ready file is to export the document as a PDF. Go to File > Export and select Adobe PDF (Print) from the drop-down menu in the Export window.
In the Export Adobe PDF window, under the General options, select [Press Quality] from the Adobe PDF Preset drop-down menu.
From the menu on the left-hand side of the window select Marks and Bleeds to open up a new set of options.
Under Marks, check All Printer’s Marks.
To ensure your carefully prepared bleed is included in the final exported file, check Use Document Bleed Settings under Bleed and Slug.
Click Export at the bottom right corner of the window to create your PDF file. Your file will now include your predefined bleed, and is ready to send to the printers.
Adding a bleed to your InDesign documents is essential when creating documents that will be printed professionally. Avoid unsightly trim errors (or even worse a lecture from your disgruntled printer!) by being sure to include a bleed in all your InDesign work. To find out more about setting up documents in InDesign, check out our detailed look at the New Document panel here. To find more useful InDesign tips and tricks pay a visit to our beginner InDesign tutorials page.