--- title: "Answers | Once Books" description: "Straight answers to the questions people ask before making a personalised book: cost, safety, timing and printing." source: "https://www.oncebooks.com/answers" --- Answers # Questions, answered plainly Straight answers to the questions people ask before making a personalised book: cost, safety, timing and printing. - [Are my child’s photos used to train AI?](https://www.oncebooks.com/answers/are-my-childs-photos-used-to-train-ai) — No. Your child’s photos are used only to build this book’s character references, and our system refuses, in code, to send those references to any AI provider that trains on user data. You can delete them at any time. - [Can I edit the story, or is it all AI-written?](https://www.oncebooks.com/answers/can-i-edit-the-story) — You’re in control of the story. You can write or adjust the text on every page, reorder pages, and regenerate any illustration. Nothing is final until you approve it. - [Can I get a printed copy of my book?](https://www.oncebooks.com/answers/can-i-get-a-printed-copy) — Every book exports as a high-resolution, print-ready PDF you can print yourself today. Professionally printed hardcover and premium gift editions are coming soon. - [Can I get a refund if I don’t like my book?](https://www.oncebooks.com/answers/can-i-get-a-refund) — Because you preview a book’s opening pages before you pay, and nothing is charged while you make it, you buy only when you’re happy. Digital purchases are generally final once delivered. Printed editions are coming soon, and their terms will be shown at checkout. - [Can I sell crossword puzzles I make with a generator?](https://www.oncebooks.com/answers/can-i-sell-crossword-puzzles-i-make-with-a-generator) — Yes. The free tool makes one puzzle for personal use, but the crossword interiors you export from Publisher Studio are yours to publish and sell on Amazon KDP. Each grid ships with its clue list and matching solution, and one unlock re-exports the book at any trim. - [Can I sell my book somewhere other than Amazon KDP?](https://www.oncebooks.com/answers/can-i-sell-my-book-somewhere-other-than-amazon) — Yes. A Publisher Studio project exports to Amazon KDP, Gelato and Kindle, so one book is not tied to Amazon alone. The interior and cover are made print-ready for whichever service you pick in the export step. - [Can I sell sudoku books I make with a generator?](https://www.oncebooks.com/answers/can-i-sell-sudoku-books-i-make-with-a-generator) — Yes. The free tool makes one puzzle for personal use, but the sudoku interiors you export from Publisher Studio are yours to publish and sell on Amazon KDP. Every board is verified uniquely solvable, and one unlock re-exports the book at any trim. - [Can I sell word search puzzles I make with a generator?](https://www.oncebooks.com/answers/can-i-sell-word-search-puzzles-i-make-with-a-generator) — Yes. Puzzles you generate from your own word lists are yours to publish and sell, including on Amazon KDP. You need a print-ready interior at a valid trim, an answer key for every puzzle, and a cover. - [Do I own my personalised book, and can I print or sell it?](https://www.oncebooks.com/answers/do-i-own-my-personalised-book) — You keep everything you upload, and generated pages belong to you for personal and commercial use, subject to the AI provider’s terms. Ownership of AI-generated images still varies by country, so if commercial rights are central to your project, check before you rely on them. - [Do low-content books need an ISBN?](https://www.oncebooks.com/answers/do-low-content-books-need-an-isbn) — No. You do not need an ISBN to publish a low-content book on Amazon KDP. Low-content books are not eligible for KDP free ISBN, so if you want one for wider distribution you buy your own, but it is optional. - [Does every sudoku have only one solution?](https://www.oncebooks.com/answers/does-every-sudoku-have-one-solution) — A proper sudoku has exactly one solution. Every board from our generator is verified to be uniquely solvable, so it is never ambiguous or unsolvable, and the printed solution is the only answer. - [How do I make a crossword with an answer key?](https://www.oncebooks.com/answers/how-do-i-make-a-crossword-with-an-answer-key) — Type each answer with its clue, and the generator interlocks them into a numbered grid, then prints the puzzle on page one and the filled solution with the clue list on page two. No sign-up. - [How do I make a word search with an answer key?](https://www.oncebooks.com/answers/how-do-i-make-a-word-search-with-an-answer-key) — Enter a list of words, generate a grid that hides them across, down and diagonally, then produce a solution page that marks where each word sits. Our free generator makes both the puzzle and its answer key in one step. - [How do I work out the spine width for my book?](https://www.oncebooks.com/answers/how-do-i-work-out-the-spine-width) — Multiply the page count by the paper thickness per page: about 0.0025 inch for cream and 0.0022520000000000005 inch for white on KDP. A 120-page white-paper book has a spine about 0.27 inch wide, which sets how wide the full cover has to be. - [How do you count the hidden cubes in a cube counting puzzle?](https://www.oncebooks.com/answers/how-do-you-count-hidden-cubes-in-a-cube-counting-puzzle) — Count the visible cubes one layer at a time from the bottom up, then add the cubes that must be underneath each raised cube to hold it up. In a fair puzzle nothing floats and the shape is one connected piece, so every tall column stands on a full stack of cubes you cannot see. - [How is this different from a template personalised book?](https://www.oncebooks.com/answers/how-is-this-different-from-a-template-book) — Template books let you pick a skin tone and type a name onto pre-drawn art. Once Books generates original illustrations from your child’s actual likeness, in any story and art style, with the same character on every page. - [How long does it take to make a personalised book?](https://www.oncebooks.com/answers/how-long-does-a-personalised-book-take) — About six minutes for a full book. Pages are generated in parallel, so you can start reviewing the early ones while the rest finish. - [How many pages is a personalised book?](https://www.oncebooks.com/answers/how-many-pages-is-a-personalised-book) — You choose the length when you create a book: 4, 8 or 12 pages. A 12-page book is the longest, and every page keeps the same character and the art style you picked. - [How many pages should a journal have?](https://www.oncebooks.com/answers/how-many-pages-should-a-journal-have) — Most journals run 100 to 200 pages. Print-on-demand services bind from 24 pages up (KDP’s window is 24 to 828), and the binding margin widens at 151 and 301 pages, so 120 pages is a common choice that keeps the gutter at its narrowest. - [How many pages should a planner have?](https://www.oncebooks.com/answers/how-many-pages-should-a-planner-have) — It depends on the layout. A monthly planner is about 30 to 40 pages, a weekly planner across 52 weeks lands near 110 to 150 pages with extras, and a page-a-day daily planner runs past 365, so daily planners usually cover a quarter, not a year. 1[2](https://www.oncebooks.com/answers/p/2)[3](https://www.oncebooks.com/answers/p/3)[Next →](https://www.oncebooks.com/answers/p/2) ## Keep reading - [The blog](https://www.oncebooks.com/blog) — Longer reads on how the books are made, what goes wrong in AI illustration, and how to choose photos, styles and formats. - [Glossary](https://www.oncebooks.com/glossary) — Plain definitions of the vocabulary: the Character Sheet, the Consistency Engine, style profiles, drift. - [Help centre](https://www.oncebooks.com/help) — Task-shaped instructions for making, printing and sharing a book once you have started one.