Definition

• An image that touches the outermost edge of a page layout is said to "bleed." Bleed allowance –– the provision for this occurrence when creating a page layout –– is an extension of the image beyond the trim line to accommodate the paper cutting variation that may occur after printing. A bleed allowance accounts for inaccuracies in the printing and trimming processes, and is a margin of error to ensure that the image prints to the very edge of the finished piece.
  
  

Bleed Size

• To create a bleed, the designer extends the image a minimum of one-eighth inch or more beyond the trim size of the piece. It is important to indicate precisely where the bleed appears with proper bleed and trim marks. These marks tell the operator where to cut the image in the trimming stage. Every document that is sent to a printer must have bleed and trim marks on it.
  
  

Document Setup

• When creating an electronic document in a page layout or desktop publishing software, you must enter a bleed margin value in your preferences or general options pane. Otherwise, the document will not include a bleed area, and objects that bleed off the page will be cropped. Nearly every software program will do this automatically; this option is usually found in a "Marks and Bleeds" pane or in the "Print" dialogue box. If your document has a bleed, and you want to export it to a PDF, you must generally set the option before you export the file.
  
  

Considerations

• Bleed marks and trim marks must appear at all four corners of the piece of art or the page layout and indicate the outside perimeter of the document. Since your bleed requirements may call for a larger press sheet and sometimes even a larger printing press, make sure that the paper size is large enough to accommodate the bleed or printer marks.