Authors design covers as three things — a front, a back, a spine — and reasonably expect to upload three things. KDP wants one thing: a single flat sheet that wraps around the finished book, printed in one pass and folded. When your cover PDF arrives with two or more pages, KDP has no way to know which page is supposed to wrap where, and the upload fails.
What KDP is actually saying
KDP’s cover guidance is built around one PDF containing the back cover, the spine, and the front cover — and the practical instruction in its cover documentation is to open the finished PDF and confirm it contains exactly one wide page. Our own preflight engine checks the same rule in the same words — “cover is a single page” — because everything else about the cover depends on it: the page’s width must equal the full wrap formula, which is how KDP verifies your spine math at the same time.
| Piece | Width (6×9″ book, 300 pages, white paper) |
|---|---|
| Bleed | 0.125″ |
| Back cover | 6″ |
| Spine (300 × 0.002252″ per page) | 0.676″ |
| Front cover | 6″ |
| Bleed | 0.125″ |
| Single-page total | 12.93″ wide × 9.25″ tall (trim height + 0.25″) |
How multi-page covers happen: (1) a designer delivers front and back as separate pages of one PDF, the way you’d deliver a brochure; (2) Canva designs built as two pages (front, back) downloaded as a single PDF — convenient, and exactly wrong for print upload; (3) an InDesign cover laid out as separate pages instead of one page at wrap size; (4) a cover PDF merged with something else — a barcode proof, a spec sheet, the interior’s first page. Even one extra page, even a blank one, fails the check.
Check it yourself
- Count the pages. Open the cover PDF in Acrobat or any reader and look at the page count: it must say 1 of 1. (Our engine literally runs this count on every cover we check.)
- Measure the one page. File > Properties shows its size. Compare against the wrap formula for your page count: 0.125″ + trim width + spine + trim width + 0.125″, and trim height + 0.25″. The spine calculator does this math for KDP and Ingram.
- Read the layout left to right. On the single page: back cover on the left, spine in the middle, front cover on the right. A page that shows only a front cover is a front cover, not a wrap — it will also fail the dimension check.
- Check for stowaways. If the count is 2 but page 2 looks empty, it still counts. Page 2 has to go.
Not sure your wrap math is right? The free check counts your cover’s pages, measures the sheet against your page count and paper, and reads the barcode zone — plus 10 more checks on both files, in plain English, free within 48 hours. Get the free check →
How to fix it
In InDesign
Build the cover as a single page sized to the full wrap (use KDP’s template for your exact page count as the underlay), with back, spine, and front positioned across it. Export that one page as your PDF — if your document has other pages, export the cover page’s range only.
In Canva
Resize the design to the full wrap dimensions as one design page — one wide canvas, not a two-page document — lay back/spine/front across it, and download as PDF Print. A two-page Canva download can’t be merged into a wrap afterwards; the geometry has to be built as one sheet from the start.
In Photoshop or Illustrator
One artboard/document at the full wrap size, 300 DPI. If you received front and back as separate files, place both (plus a spine strip) onto the single canvas at their exact positions — don’t just append one PDF to the other.
If someone else made your cover
Ask for “the print-ready wrap: one PDF, one page, sized [your numbers] with 0.125″ bleed.” A designer who works in print will recognize the sentence instantly.
The honest limit
One page is necessary, not sufficient: a single page at the wrong size fails the dimension check instead, and a correct-size wrap built on a stale page count puts the spine in the wrong place — which is why the interior must be final before the cover is built. If your page count changes by more than a few pages, rebuild the cover; don’t stretch the old one. The free check verifies the pair together precisely because cover and interior fail as a couple, not as strangers.
Or send us the files — the check is free
Email your interior and cover PDFs and we'll tell you exactly what's wrong — in plain English, free, within 48 hours. If it does need fixing, the by-hand fix is $19 and we redo it free if KDP rejects it for a formatting issue we were hired to fix. We rebuild files to be compliant with KDP's published spec — that's the promise we can keep.
Prefer the whole library in one file? The KDP Rejection Field Guide (free PDF) collects every guide, table, and the 13-point checklist.
More from the Help Library
- The KDP & IngramSpark Help Library — all guides & tools
- Spine width calculator — KDP and IngramSpark math
- Spine text error — too close to the edge, or a spine too thin for text
- Barcode rejected / ISBN mismatch — digit for digit
- Bleed error — “your file does not include bleed”
- Page size does not match the trim size you selected
- The free rejection check — all 13 checks at once