Glossary · Printing & files
What is an interior PDF?
Definition
Interior PDF: The interior PDF is the print-ready file of a book's pages, sized to the trim size with fonts embedded, that a printer uses to print the inside.
For a print book you upload two files: the cover and the interior. The interior PDF contains every page of the book in order — front matter, chapters and back matter — laid out at the exact trim size, with proper margins and page numbers. It is what the printer actually prints on the inside pages.
A print-ready interior PDF has a few requirements that a manuscript does not. The page size must equal the trim size (plus bleed if any images run to the edge). All fonts must be embedded, so the printer does not substitute them. Images should be high resolution for print — 300 dpi is the common guideline. Margins, including the wider gutter on the binding side, must meet the printer's minimums. Chapters usually start on a right-hand page, which can add blank pages.
Some printers, such as IngramSpark, prefer a specific PDF standard such as PDF/X-1a, while others accept ordinary PDFs that meet their specifications. Check the platform's current file requirements before exporting.
Do not upload a Word document's default Letter or A4 pages as your interior — the printer will either reject it or shrink it to fit. After uploading, use the platform's online previewer to page through every spread, and order a proof copy before you publish.