Guides

How to make a print-ready PDF of your book

A printer's automated check reads a PDF the way a machine does: page size, fonts, image resolution, marks, transparency. It never looks at the design. Here is what it looks for, and how to inspect a PDF yourself before uploading it.

What "print-ready" means

A print-ready PDF has every decision already made. The page is the size of the finished book. The type is the exact typeface, embedded so it cannot change. Images are at print resolution. There is nothing in the file that a press cannot use: no comments, no bookmarks, no form fields, no layers, no crop marks the printer did not ask for. The file that comes out of the printer is the file that went in.

The checklist

1. Page size. Every page is exactly the trim size (6 × 9 in, for example), or exactly trim plus 0.125 in bleed on three sides (6.125 × 9.25). All pages the same size. Not US Letter, not A4, not "close".
2. Fonts embedded. All of them, including the ones used for a single ornament or a page number. Subset embedding is fine. IngramSpark specifically warns that some export presets skip the fourteen base fonts (Times, Helvetica, Courier and their variants). Those must be embedded too.
3. Images at resolution. 300 pixels per inch at printed size for photographs and grayscale art; 600 for pure black-and-white line art. A 1200-pixel-wide photo printed 4 in wide is exactly 300 ppi; printed 6 in wide it is 200 and will look soft.
4. Transparency flattened. Drop shadows, soft edges and semi-transparent fills need to be baked into the page. Most exporters do this when you choose a PDF/X-1a preset.
5. No marks. No crop marks, registration marks, color bars or slug information. The printer adds its own.
6. No extras. No bookmarks, annotations, comments, hyperlinks, form fields, hidden text or layers. No password or encryption.
7. Black text is black. Body text should be 100 percent black, not a rich black built from four inks, and not a very dark gray. Rich black text prints fuzzy on a press.
8. Blank pages are blank. A blank page has nothing on it, not a page number, not a running head. KDP flags more than four blank pages in a row and more than ten at the end.
9. Metadata matches. The title, author and ISBN in the file match what you entered when setting up the book.

How to inspect the file

Page size. On a Mac, open the PDF in Preview and press ⌘I for the Inspector; the page size is listed in inches or points (72 points per inch, so 6 × 9 in is 432 × 648 pt). In Acrobat it is under File → Properties. Check the first page, a chapter opener, and the last page: all identical.

Fonts. Acrobat's File → Properties → Fonts tab lists every font and says "(Embedded)" or "(Embedded Subset)" after each one. Any font without that label is a rejection waiting to happen. Free alternatives such as pdffonts on the command line show the same list with an "emb" column.

Images. Zoom to 400 percent on a photograph. If it looks soft or blocky on screen at that zoom, it will look soft in print. Acrobat's Print Production → Preflight has a profile that lists images under 300 ppi.

The printer's check. Both KDP and IngramSpark run their own preflight on upload and report problems in plain language: fonts not embedded, content in the bleed area, low-resolution image on page 87. Upload early, read the report, fix, upload again. There is no charge for re-uploading before publishing.

Proofs

A file can pass every automated check and still print badly: a gutter that is technically legal but swallows the text, a spine that looks fine on screen and is a hair off in the hand, a photograph whose midtones went muddy. Order a printed proof. Both services sell one at print cost. Page through it with a pencil, fix, upload again. A second proof is cheap next to a run of copies that all have the same flaw.