KDP error guide
Why KDP says your gutter is insufficient
Find pages whose inside margin is too small for the selected binding and page count.
Technically reviewed · September 1, 2026
What this issue means
The required inside margin changes with page count. A visual estimate is unreliable because odd and even pages swap the bound edge; the report measures the correct edge for each page.
What BookPreflight checks
- Final page count and binding direction
- Inside-edge content bounds on odd and even pages
- Whether shifting or proportional scaling would lose content
How to correct the source file
- 1
Correct mirrored margins in the source document.
- 2
Increase the inside margin without shrinking text below an acceptable size.
- 3
Export again and recheck all pages, not only the flagged sample.
Verify the exported PDF, not the preset name
Keep the editable source and original PDF. Export a new file, run the complete scan again and review every remaining finding. A repair is only labelled safe after loss checks and a full deterministic post-flight.
BookPreflight is an independent tool. It is not affiliated with or endorsed by Amazon or Kindle Direct Publishing, and it cannot guarantee acceptance.