GridbinderGuide · KDP rules
Are puzzle books low content on KDP?
"Low content" is a common name for puzzle and activity books in self-publishing circles, but KDP uses the term for something narrower. The difference decides whether you get an ISBN, a series and a Look Inside preview.
Updated 29 October 2026 · Examples are real, unedited pages from the Gridbinder studio unless the caption says otherwise.
What KDP says
KDP's help page on low-content books defines them as books with "minimal or no content on the interior pages", which are "generally repetitive, and designed to be filled in by the user". Its examples are notebooks, planners, diaries and journals, prompt journals, log books and blank sheet music.
The same page has a list of books that are not generally low-content: novels, nonfiction, puzzle books, coloring books, children's books, manuals and others. It adds that this "does not typically include activity books, such as puzzle books or coloring books", and that there can be exceptions.
What changes if a book is low content
| Low-content book | Normal paperback (e.g. a puzzle book) | |
|---|---|---|
| ISBN | Optional; no free KDP ISBN | Required; free KDP ISBN available |
| Series | Not eligible | Eligible |
| Look Inside / sample | Not supported when published without an ISBN | Available |
| Barcode | KDP prints one in a 2 x 1.2 in box when there is no ISBN | From the ISBN |
| Review time | KDP mentions 3 to 4 weeks for low-content books when volumes are high | Usually up to 72 hours |
If a book is low content, KDP asks you to tick the low-content box in the categories step; it says a low-content book set up otherwise will be rejected. That is why the setting matters.
Why publishers get confused
On the KDP forum, publishers of monthly Sudoku and word search books report being told their books are low content and cannot form a series, while the help page says puzzle books are not generally low content. The "exceptions" sentence leaves room for KDP to decide case by case. What the help page rewards is content: real puzzles, each different, with instructions and solutions, are content. A book of repeated templates with little in them is closer to low content.
Practical advice
- Set up a puzzle book with real puzzles, how-to pages and solutions as a normal paperback, with an ISBN.
- Make each volume of a series different: new puzzles, not the same ones in a new cover.
- If KDP disagrees with your setting, reply with a short description of the contents and ask which setting it wants. Keep a record.
- Do not tick low content just to skip the ISBN; you lose the series and the Look Inside preview.
This is a summary of KDP's help pages as of 29 October 2026 and of what publishers report on the forum, not legal advice. KDP decides how each book is classified.
Questions
Is a Sudoku book low content?
KDP lists puzzle books as not generally low-content. A Sudoku book with real puzzles and solutions is usually published as a normal paperback with an ISBN.
Can a puzzle book be part of a KDP series?
Low-content books cannot. Puzzle books are not generally low content, so they can, but some publishers report KDP blocking puzzle series; reply to KDP with a description of the contents if that happens.
Do low-content books need an ISBN?
No. Low-content books do not require an ISBN and are not eligible for a free KDP ISBN.
Sources
- KDP: Low-content books, checked 29 October 2026
- KDP: Start a book series, checked 29 October 2026
- KDP: Timelines, checked 29 October 2026
- KDP Community: Series for Sudoku books?, checked 29 October 2026
- KDP Community: Series blocked, checked 29 October 2026
KDP changes its rules from time to time. If a number here and the KDP help page disagree, the KDP page wins; please tell us at support@arling.sk.