KDP offers free Microsoft Word templates for paperback interiors. They are a good start, and only a start: a template sets up the page, and the book still has to be fitted into it.
What a template gives you
- Blank templates have the page size and margins set.
- Templates with sample content add formatted front matter, such as a title page and a table of contents, and chapters with placeholder text.
The most common trim size in the US is 6 × 9 inches, and there are templates for other trim sizes as well. For pages with bleed, the page has to be larger than the trim size, and the file has to go to KDP as a PDF.
What you still do yourself
KDP's own list, from its template page:
- Remove every piece of sample text and every placeholder.
- Add or delete chapters to match your book.
- Replace the title and author in the headers, matching your title setup in KDP.
- Add the page numbers to the table of contents once the rest of the book is finished.
- Use images of at least 300 DPI and text of at least 7 points.
- Save as a PDF with the fonts embedded.
What a template cannot know
A template's margins are set once, before your text is in it. KDP's minimum inside margin depends on the page count: 0.375″ up to 150 pages, rising in steps to 0.875″ above 700. The page count is known only when the whole book is laid out.
So check the inside margin against KDP's table once the page count is final. If the book crosses into the next band, widen the margin, lay the book out again and check once more. How KDP gutter margins work explains the loop, and the margin calculator gives the minimum for any page count.
Pasting a finished manuscript into a template also brings its own formatting along. Headings, spacing and fonts then have to be matched to the template's styles by hand.
Without a template
Torcul starts from the manuscript you have, a Word or Markdown file. It shows how each heading was read, lays the book out at the trim size you choose, and fits the inside margin to the final page count. It then checks the finished PDF, and makes the EPUB and, if you want one, the cover.
Sources
None of this guarantees that KDP will accept a file. KDP changes its help pages, so check the date on this one and on any report a tool gives you.