One of our most popular issues people have with rejection on KDP is it expects a different size then you uploaded. One of the most popular reasons why this happens, especially with newer people, is they pick "Paperback: Interior" and make another project "Paperback: Cover" without understanding the implications.
In short, always pick Cover and Interior, until at least you are well versed in KDP, their requirements, what they expect, and the reasons why you would pick Cover or Interior only which we will explain later some reasons you might do this. Odds are probably 99.9% you need to pick a project that is Cover and Interior if you are new to the KDP Publishing world.
As mentioned in these 2 troubleshooting articles, Cover Issue's with KDP and Interior Issue's with KDP, we say this:
If you are reusing an interior for a low content book and just making a different cover, or, just like to make your interior and cover seperate for some reason, and you pick Cover only, you must enter the number of pages your interior is. Do not leave it on default of 24 pages or enter a random number you think your interior will end up. If you insist on doing these seperatly, finish the interior first, so you know how many pages it is, then create your cover only and enter the interior number of pages. A 100 page interior will not fit inside a cover made for 24 pages.
If you do create a Cover and Interior project and add or delete pages, the cover size changes according to what KDP specifies. So picking this type of project, means less headaches and possible rejection by KDP.
So until you understand and know the inner workings of KDP and requirements they have for books, just pick Cover and Interior Project when creating your projects, it will probably save you time in the end and less chance for rejection from KDP by doing so.
If you do want to do a cover and interior seperate for whatever reason, then you need to complete your interior first, so you know the number of pages it is, so you can enter that number into the number of pages part when you create a Cover only project. You may think at the start you know you are making a 80 page interior, then you get it done, and think, oh I want to add a this book belongs to on page 1, and then on page 3 you want to thank people for buying the book and add a qr code to your author page. Then you want to add 20 pages of ruled paper at the end because you learn printing cost for a 8.5" x 11" paperback is the same for 80 pages as it is 108 pages. Then all of a sudden your book is now 108 pages and not 80 pages. You Cover only project set to 80, now has to be redone in a Cover only project for 108 pages.
Reason you may want to create a cover only project is:
- You have for example a lined interior done and you want to make 3 or 4 different covers and reuse that same interior. Again be sure to set the number of pages for the cover to the exact number of pages the interior is.
- You have done a written book in Micrsoft Word, or Google Docs or some other word processing program. You don't need to upload the interior to the Book Bolt studio, you just save it as a PDF. Then use the studio to create a cover only for it. Once you know the final number of pages it is, you can create a cover only project and then enter the number of pages the project is.
Reasons you may want to create a interior only project is:
- Simular to above, you want to create say 3 or 4 notebooks, the interior is exactly the same for each and the cover will be the only thing different.
If you pick Custom Size from the studio for whatever reason, you need to get the specifications from KDP to setup your book right. For Example, you want a book to be 7.75" x 10.25" as your final product size, you should not enter those numbers you need go to KDP on their page Set Trim Size, Bleed, and Margins and get the dimensions to enter, so that in the end your book will end up as 7.75" x 10.25".