KDP compared the uploaded cover sheet against the spine it expects for the book and the widths did not match. The fix is to recalculate the wrap from the final interior instead of stretching the artwork.
KDP rejected my cover for spine widthKDP compared the uploaded cover sheet against the spine it expects for the book and the widths did not match. The fix is to recalculate the wrap from the final interior instead of stretching the artwork.
Why this happens
KDP derives the expected spine from the final interior page count and the selected paper, then checks the uploaded cover sheet against that width. If the interior was reformatted after the cover was built, or the paper, trim, or binding changed, the uploaded spine no longer matches what KDP expects.
The complete manual fix
Open the formatted interior PDF and note its exact final page count. Use the PDF's own total, not the manuscript estimate.
Confirm the trim size, binding, and paper that are actually selected in the KDP title setup.
Recalculate the spine: page count multiplied by 0.002252 inches for white and standard-color paper, 0.0025 for cream, or 0.002347 for premium color.
Rebuild the full cover sheet at the new dimensions: two trim widths plus the recalculated spine plus 0.25 inches of total outer bleed wide, and trim height plus 0.25 inches tall.
If the book is 79 pages or fewer, remove all spine text. Above that, keep 0.0625 inches of clear space on each side of the spine lettering.
Export a fresh PDF and compare its page size against KDP's newly generated template before uploading again.
Keep the evidence
Save KDP's written notice, the unchanged exported file, the selected print settings, and the template used for comparison. Those records make a support case reproducible, and they are what the technical spec guarantee asks for.
Recalculate before rebuilding
Spine width0.757 in
Full cover13.007 × 9.250 in
At 300 DPI3,902 × 2,775 px
Spine textAllowed
Calculated from KDP's current paperback formula. Confirm against your printer's generated template before upload.
Enter the final trim, binding, paper, and page count in Coverfairy and the complete KDP sheet, spine, and bleed are recalculated while the artwork and typography stay editable. An active pass includes paperback and hardcover PDFs with live preflight checks.
The pass is covered by the technical spec guarantee: if KDP rejects an unchanged Coverfairy export because Coverfairy calculated the trim, bleed, spine, or sheet dimensions incorrectly, Coverfairy corrects the file or refunds the affected pass.
