Printing Terminology: Signatures

Shows multi-up on a press sheet, example of imposition in printing.

Like so many words in the English language, signature is a term that has a multiple meanings. To the average person, a signature is how you write your name when signing a document. To a commercial printer, signature has a different meaning altogether.

What is a Signature in Printing?

A somewhat related printing term we discussed previously is imposition. Imposition is the arranging of pages prior to going to press such that after being printed, a few folds and cuts will make the pages appear in proper sequence when gathered for a book or magazine. A signature, in printing terminology, is the number of such pages that can be arranged and printed on a press during a single press pass. The larger the press, the greater number of pages that can be included in the signature.

Multiples of Four

Signatures are always designated by a number that is a multiple of four. Hence, 4, 8, 12, 16, 24, 32, and 64 are common signature numbers. Signatures on any given press will vary according to the size of the page to be printed. For instance, on a smaller press that accommodates 11” x 17” paper sheets, a signature for a book or magazine with 8.5” x 11” pages would be 4; for a book with 5.5” x 8.5” pages, the signature would be 8.

Planning Ahead

When designing your book or magazine, it’s helpful to make sure your page counts are multiples of four. In instances where the page count is not a multiple of four, whether by falling short or exceeding a multiple by one or two pages, the issue can be resolved simply by adding a few blank pages to be inserted at the end of a book. Or, in the case of a magazine, by adding or removing content. By keeping page counts in multiples of four, your printer will be able to offer the most economical pricing for your project.

Submitting Files for Printing

Because most commercial printers use proprietary software to arrange pages for imposition on the signature, it’s best to submit your finished documents (typically in PDF form) as sequentially numbered pages. Talk with your printer before you begin a book or magazine project and they will guide you through the process.

If you have any questions about Signatures, give us a call at 330-597-8560. We’re happy to help you get the most out of your print projects!