FormatPaperback

FormatPaperback checks your interior PDF for Amazon KDP paperback formatting problems and finds the pages KDP would reject. It reviews margins, gutter, trim size, page count, and fonts page by page. You can then fix margins, gutter, trim size, and page count in one click, all in your browser.

The check is free, and there is no account or upload required because your manuscript never leaves the browser. Paid downloads cost $9 per book and include the fixed interior file and a full-wrap cover with the exact spine width calculated for your page count. Settings include a range of KDP trim sizes, black-and-white and color paper options, and a margin buffer that can be set to safe or tight.

The tool is built for self-publishing authors, novelists, workbook creators, and anyone preparing a paperback for Amazon KDP who wants to avoid rejected uploads and manual reformatting in Word or Vellum.