How to prepare a print-ready PDF for your book

Print-ready means your PDF needs no further work before it goes on press. In practice that is a short, strict checklist: the document is the exact finished trim size, artwork that runs to the edge includes bleed, every font is embedded or outlined, images are high enough resolution, colours are in the printer's colour space, and the file is built as single pages rather than reader-style spreads.

It is worth separating the interior from the cover, because they have different rules. The interior is a single-page document at trim size; the cover is one flat spread, front, spine and back together, with bleed on every outer edge. Our Interior PDF Checker and Cover PDF Checker reflect this split, so you can verify each file against the right set of checks rather than a generic one.

Trim size is the finished dimension of your book after cutting, for example 198 x 129mm or a square 210 x 210mm. Your document must be set up at that exact size from the outset. Resizing or scaling a finished PDF to fit is a common cause of subtle errors, so choose the correct size before you lay anything out.

Bleed is extra artwork, normally 3mm, that extends beyond every outer trim edge. Industrial guillotines cut through stacks of books and can shift very slightly, so any background colour or image that is meant to reach the edge must run 3mm past it. Without bleed, that tiny shift leaves a thin white sliver along the edge. Equally, keep important text and page numbers a few millimetres inside the trim, in the safe margin, so nothing critical is cut off. Bleed applies to the cover and to any interior page with edge-to-edge artwork; a plain text page needs none.

If your fonts are not embedded in the PDF, the printer's system may substitute different ones, quietly changing your line breaks, spacing and overall look. Embedding stores the font data inside the file so it prints exactly as you designed it. The reliable alternatives are to embed all fonts on export or to convert text to outlines (vector shapes), though outlining means the text is no longer editable, so keep an un-outlined master.

Transparency, drop shadows, soft glows, semi-opaque layers and certain blend effects, can occasionally render unpredictably on press or in older print workflows. Flattening transparency on export resolves these effects into a stable, predictable result. Exporting to a PDF/X standard such as PDF/X-1a handles both concerns at once: it forces fonts to embed and flattens transparency, which is exactly why it is a safe default for print.

Screens display colour in RGB; presses print in CMYK, the four-ink model of cyan, magenta, yellow and black. If you send RGB artwork, it has to be converted somewhere in the chain, and bright RGB colours can shift, often looking duller or different from your screen. Converting to CMYK yourself before export gives you a more accurate, predictable result and avoids surprises on the printed cover. For mono interiors, make sure black text is genuine black and your file is set up accordingly.

Image resolution should be at least 300dpi at the final printed size. An image that looks crisp on screen at 72dpi can print soft or pixelated once enlarged on paper. Avoid stretching small web images to fill a page, and check the effective resolution after scaling, not before. Our Print-Ready PDF Checker and Cover PDF Checker both flag low-resolution images and RGB colour, because these are two of the most visible problems in a finished book.

Export your interior as single, sequential pages in reading order, not as facing-page (reader) spreads. Printers impose the pages themselves, arranging them on large sheets in the correct order for binding. A file exported as spreads, with two pages side by side on one sheet, disrupts that process and is a frequent cause of rejected interiors.

The cover is the deliberate exception. It should be supplied as one flat spread: back cover on the left, spine in the centre, front cover on the right, with bleed around the outside. Getting that spread the right total width depends on an accurate spine, which is calculated from your page count and paper, so build the cover document from our Cover Template Generator to get the dimensions right before you design.

In Microsoft Word, set the page size to your trim size under Layout, then export with File, Save As (or Export), choosing PDF and the highest-quality option. Word does not handle bleed or CMYK natively, so it suits plain text interiors better than covers; if you need bleed, prepare the cover elsewhere. Always embed fonts (Word does this when you choose the standard PDF export rather than a minimum-size one).

In Adobe InDesign, use File, Export, choose Adobe PDF (Print) and the PDF/X-1a:2001 preset, then set bleed to 3mm on all sides under Marks and Bleeds. This embeds fonts, flattens transparency and outputs CMYK in one step. Affinity Publisher offers the same control: set up the document with 3mm bleed, then File, Export, PDF, and pick a PDF/X or press-ready preset. In Canva, design at the correct size, enable Show print bleed in the layout settings, then Share, Download, PDF Print with crop marks and bleed switched on; convert to CMYK afterwards if your printer requires it, as Canva exports RGB.

Whichever tool you use, the reasons files get rejected are predictable and avoidable: no bleed on edge-to-edge artwork; the wrong trim size or a document scaled to fit; fonts not embedded; RGB instead of CMYK; images below 300dpi; an interior exported as spreads rather than single pages; or a cover with the wrong spine width, which throws out the whole spread. Run your interior through our Interior PDF Checker and your cover through the Cover PDF Checker before submitting, and ask your printer to confirm their exact requirements if you are unsure, as safe margins and accepted PDF standards vary slightly between presses.