How to create a print-ready PDF of your book: from manuscript to print file

A finished manuscript becomes a printed book through one file: the print-ready PDF of the interior. "Print-ready" is not a compliment; it is a specification, and Amazon KDP publishes it in detail. Every platform rule below is quoted from KDP's own help pages, fetched for this guide. The process around the file, account, metadata, ISBNs and royalties, is how to publish on Amazon KDP; the double-spaced document agents request is a different format entirely, covered in how to format a manuscript.

What a print-ready PDF actually is

KDP's paperback submission guidelines describe the file precisely. It is a single-page PDF: KDP requires "single page files (as opposed to spreads or 2-up files)". "Embed all fonts and images in your native file prior to submission", because "our printing presses need information about how to properly render the fonts used in your file". Images need at least 300 DPI. The file carries no crop marks, trim marks, bookmarks, comments or annotations, and must not be locked or encrypted. Total size stays under 650 MB. Each of these is on KDP's list of common points of failure.

Choose the trim size before you format the book for print

Everything later hangs on the trim size, which is why KDP's instruction is to pick it first: "Set your trim size before you set your margins, since margin size depends on page count and on whether you have elements that bleed." Page size, gutter minimums and allowed page counts all depend on it. KDP's standard paperback trims are 5" x 8", 5.06" x 7.81", 5.25" x 8", 5.5" x 8.5" and the 6" x 9" default. Large trims, wider than 6.12" or taller than 9", run up to 8.5" x 11". Custom paperback sizes are allowed between 4" and 8.5" wide and 6" and 11.69" tall. Page counts run 24 to 828 on white paper with black ink (hardcover runs 75 to 550), and page count is rounded up to an even number. Changing trim after layout reflows every page, so it is the first decision, not the last.

Margins, mirroring and the gutter

A bound book does not open flat: the spine's curve swallows anything set too close to it. "A gutter margin is extra space on the inner edge of a page, used to account for a binding" (Butterick's Practical Typography), and in a two-sided book it alternates sides, which means mirrored margins, larger inside than outside. KDP enforces the gutter by page count:

• 24 to 150 pages: inside margin 0.375" (9.6 mm)
• 151 to 300 pages: 0.5" (12.7 mm)
• 301 to 500 pages: 0.625" (15.9 mm)
• 501 to 700 pages: 0.75" (19.1 mm)
• 701 to 828 pages: 0.875" (22.3 mm)

Outside margins must be at least 0.25" without bleed and 0.375" with it, and top, bottom and outside margins need not be equal as long as each meets its minimum. Treat these as floors, not targets: a 400-page book held open at the minimum gutter is a book the reader fights.

Print typography: font, size, spacing, numbers

The interior's job is comfortable reading at physical size.

• Body font. A text face; KDP names candidates directly: Centaur, Garamond, Hightower Text, Palatino Linotype, Constantia, Cambria. Display faces belong on headings. KDP's minimum font size is 7 points, a caption floor that body text sits well above.
• Line spacing. "For most text, the optimal line spacing is between 120% and 145% of the point size" (Butterick). At 11-point type that gives roughly 13 to 16 points of spacing. Single and double spacing are typewriter settings; books live between them.
• Line length. "Aim for an average line length of 45-90 characters, including spaces" (Butterick). This binds font size, trim and margins into one decision: long lines mean wider margins or smaller type.
• Real bold and italic. KDP warns that "faux" bold or italic, synthesized by software instead of existing as real fonts, "sometimes causes production failures".
• Page numbers. Sequential, even numbers on left-hand pages for left-to-right text, roman numerals allowed at the start, Arabic numerals in the body.

Front matter and back matter, in order

KDP publishes a canonical order for the interior: half title, title, copyright, reviews and praise, dedication, table of contents, preface, acknowledgments, prologue, introduction, then the body, then back matter. The title page "always falls on a right-facing page directly after the half title page", carrying title, subtitle and author name, without the word "by". The copyright page "always falls on the first left-facing page after the title page". Half title, copyright and table of contents pages carry no page numbers or headers. The table of contents "includes chapters and section names as they appear in the body of the manuscript": generate it after the body is final, never before, or its page references are fiction. Back matter starts its first section on a right-facing page; the author bio and the index also fall on right-facing pages. A short novel can skip the half title, reviews and preface; the order of what remains does not change.

Bleed: only when ink reaches the edge

Bleed is ink that runs past where the paper will be cut. KDP trims 0.125" (3.2 mm) from the top, bottom and outside edges of every page, so an image meant to reach the edge must extend past the trim line by that amount, and the PDF page grows to hold it: trim height plus 0.25", trim width plus 0.125". A 6" x 9" trim with bleed becomes a 6.125" x 9.25" PDF page. If even one page bleeds, the entire file must be set up with bleed, and then the interior must be uploaded as a PDF. Without bleed, KDP also accepts DOC, DOCX, RTF, HTML and TXT and converts them itself, adding a reflow step you do not control. Plain prose interiors need none of this. The cover, a separate file, always requires bleed.

The PDF export itself

Export from a tool that controls page geometry: a word processor with the page size set to the exact trim, or dedicated book-layout software. KDP's page for Word files is blunt: "For paperbacks, PDFs is preferable to Microsoft Word documents." Use Print to PDF rather than Save As PDF, so images remain at 300 PPI. Pick a press preset: PDF/X-1a where offered, otherwise High-Quality Print or Press Quality. Set the page size in the PDF printer's properties to the trim. Embed the fonts rather than trusting defaults, and remember that Word repaginates depending on the default printer, the same reflow risk in a different coat. Kindle Create can prepare paperback interiors, but not ones with tables, footnotes or bleeding images. Whatever leaves your hands, keep the source document archived beside it (exporting and backing up your manuscript): the file you can re-export is the file you can fix.

Final checks, and how the platform validates the file

Run this list against the finished PDF, not against your memory of it:

1. Fonts embedded. In Adobe Acrobat, File, Properties, Fonts tab: "Every font in the list needs to show 'Embedded' or 'Embedded Subset' for your file to work."
2. Page size. Equal to the trim size exactly, or trim plus the bleed arithmetic above.
3. Page count. Even, and inside the range for your paper, ink and trim.
4. Order and placement. Title page on a right-facing page after the half title, copyright on the first left-facing page after it, contents matching the body's chapter names.
5. Cleanliness. No crop marks, bookmarks, comments or encryption; images at 300 DPI or better; size under 650 MB.

Then let the platform check it too. KDP's Print Previewer "shows you what your paperback will look like before you publish it" and "checks for errors you need to fix before submitting for publication", and you can order a physical proof copy before going live. After submission, KDP manually checks the interior and cover files and emails instructions if it finds issues. The proof is the one check no software replaces: the book as a bound object, gutter, margins, paper and all. When the file passes, the rest is the platform walkthrough in how to publish on Amazon KDP; the wider production picture is how to self-publish a book.