KDP error guide
Check effective image DPI page by page
Calculate effective image resolution at the size actually placed on each page.
Technically reviewed · September 1, 2026
What this issue means
Pixel dimensions alone are insufficient. Enlarging a small image lowers effective DPI, while cropping can change the printed result; page evidence keeps those factors together.
What BookPreflight checks
- Pixel dimensions and placed size
- Horizontal and vertical effective DPI
- Affected page and image region
How to correct the source file
- 1
Replace the source image with a higher-resolution original.
- 2
Reduce its placed dimensions without distorting the layout.
- 3
Avoid repeated recompression during export.
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.