What Does "Bleed" Mean in Printing?

Over the centuries, professional printing has developed a lot of niche industry terms. Many of them are pure shoptalk, and aren’t necessary to know unless you’re the one running the presses. However, others can be extremely useful for printshop clients. Understanding the terms related to file formatting in particular can help ensure the design hand off goes smoothly and prevent visually distracting mistakes.

Over our next few articles, we’re going to break down the print terms bleed, margin, and gutter. To learn more about how to design for margins and gutter specifically, you can check out this piece. As for this article, we’re going to focus entirely on the subject of bleed. Read on to learn what this term means in printing, the impact it has on your print designs, and whether you need to worry about it for your next project.

How Bleed Affects Your Print Project

At Wallace Carlson, we describe bleed as “a term that refers to printing that extends beyond the trim edge of the project, so the edge can be trimmed and no unprinted area remains.”

In other words, it’s a portion of the print design that ultimately gets cut off, ensuring the final product has uninterrupted printing all the way to the edge. Take a look at this finished portfolio cover as an example:

To ensure the photo extended all the way to the edges of the final cover dimensions, the original print actually went all the way into the red bleed area. Then, during finishing, the cover was cut along the yellow trim edges to produce the final result.

Consequences of Not Using Bleed

At first, bleed can seem unnecessarily wasteful. Why not just print to the final dimensions exactly and save on ink? However, even the most precise modern printing presses can’t achieve consistent edge-to-edge prints without bleed. As paper is fed into the press and mechanically manipulated, a small amount of shifting is unavoidable. So, if you were to only print up to the trim line, a variable amount of blank space between the end of the design and final trim lines would be the result. You can see this difference illustrated in the two images below.

Of course, these consequences only apply when the printing needs to extend to the absolute edges of the page. If the design is fully contained within the trim edges, like with the packaging example below, then no bleed is necessary.

The Role of Bleed in Different Print Materials 

Full bleed (where the design extends to all trim edges) or partial bleed is used whenever an image or design element needs to extend to the edge of the final print. It’s particularly common for publication covers that feature photographs, packaging with all-over patterns or gradients, and items that aren’t typically designed with borders like calendar illustrations and catalog spreads. 

If you aren’t sure if your design should include bleed, you can ask your print partner for clarification. They may even be able to help you adjust your file, and give advice on other common print design mistakes to watch for.

Setting Up Bleed: The Design Process

Setting up bleed isn’t particularly difficult. In fact, some design platforms do it for you automatically. You can also find official guides from many of the most popular design programs like Adobe Illustrator, and Adobe InDesign. However, even if you’re working in a program that doesn’t handle bleed automatically, you can still set it up yourself. You just need a means to adjust the final physical measurements of your file.

For example, these are the general steps for adding bleed to an existing document in Adobe Photoshop:

Step 1: Go to the View menu and turn on Rulers.

Step 2: Add a guideline to each of the four edges of your document by clicking on the rulers and dragging the guidelines into place.

Step 3: Go to the Image menu and select Canvas Size.

Step 4: Increase the canvas size by .25” for both dimensions*.

Step 5: The guidelines will now show the trim lines for your printing, with the space between the guidelines and the edges constituting the bleed area.

*Note: By increasing the canvas height and width each by .25 inches, you add .125” on each side. That measurement of .125” (1/8”) is the standard bleed measurement required by most US printers.