Unique puzzles, with a certificate. Preflight before you export.

I do not want two of my books sharing a grid. Amazon notices that before readers do.

Book Studio hashes each puzzle and checks it against this book and your other SmartKDP projects. Identical content gets flagged. The uniqueness certificate goes in the KDP upload package on Publisher and Studio.

Before export it runs the checks Amazon runs. Bleed, trim, spine, resolution. Print-ready means the file is actually ready. Passing preflight does not guarantee KDP will accept a book, but you find out here, not in a rejection email.

If you publish low-content, this is the part I wish existed when I started.

https://smartkdp.com