Guides · Cover & Spine

How to fix "cover dimensions are incorrect"

Updated October 28, 2026 · Amazon KDP · IngramSpark · Barnes & Noble Press · Lulu

A paperback cover isn't the size of your book. It's the back, spine and front laid out flat, plus bleed, and it has to be exact.

The error: “The cover file dimensions do not match the required size for this book”

The cover file dimensions do not match the required size for this book

Paraphrased. Each printer words this a little differently.

Quick fix: SparkPrep scans your cover and interior against the exact platform rules, pinpoints the issue, and fixes it for you with one click.

👉 Fix your file instantly at sparkprep.legenddary.com

Why you get “The cover file dimensions do not match the required size for this book”

The full cover size depends on three things: your trim size (like 6" x 9"), your spine width (from page count and paper) and bleed (0.125" around the outside). For a 6" x 9" paperback the height is 9.25", and the width is 0.125" + 6" + spine + 6" + 0.125".

If any one of those is off, even by a fraction of an inch, the printer's system rejects the cover. The most common causes: making the cover at trim size with no bleed, using the wrong paper type, or the page count changing after the cover was made.

How to fix “The cover file dimensions do not match the required size for this book” manually (the hard way)

If you want to try adjusting the files yourself, here are the steps you need to follow:

Note your trim size, your final page count and your paper (white or cream).
Get the exact full cover size from your printer's own cover calculator or template.
Open your cover file and change the document size to exactly that width and height.
Move the back, spine and front art so each panel sits in the right place, then re-export as PDF/X-1a:2001.
Re-upload it to your printer and wait for the file review again. If it fails, you start over.

You can fix this by hand with the steps above. Or drop your file into SparkPrep and let it find the problem and fix it for you, in minutes. Try it on your file.

How to fix it instantly (the SparkPrep way)

If you don't have expensive design software, or you just want to get your book published without the headache, let SparkPrep handle it.

SparkPrep was built by a self-published author whose own book was rejected 18 times. It checks your files against the exact print rules Amazon KDP, IngramSpark, Barnes & Noble Press and Lulu publish.

When you upload your file to SparkPrep:

We automatically scan for page size, bleed, spine width, safety margins, ink coverage and embedded fonts.
We explain any hidden errors in plain English.
We fix what can be fixed automatically, tell you exactly what's left, and export a print-ready PDF/X-1a, checked again before you download it.

Stop fighting the bots. Drop your file into SparkPrep today and get back to marketing your book!

Fix my cover size

What it costs to get this fixed

	Hire a professional cover designer	SparkPrep
Price	About $930	One price per book for the cover, the inside pages, or both
Time	Book a freelancer, wait for their schedule, then go back and forth on changes	Upload and get your fixed, print-ready files in minutes
Printer check	Depends on the freelancer	Checked against your printer's own rules, every time

Freelancer prices are Reedsy's own published figures (source). A great designer is worth it for original artwork. If you just need your files right for the printer, you don't need to pay designer prices.

Quick answers

What size is a 6x9 paperback cover?

The height is 9.25" (9" plus 0.125" bleed top and bottom). The width is 12.25" plus your spine width, because it's 0.125" + 6" + spine + 6" + 0.125".

Why did my cover size change?

Spine width depends on page count and paper. If either changes, the full cover width changes too.

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SparkPrep is an independent tool and is not affiliated with Amazon KDP, IngramSpark, Barnes & Noble Press or Lulu.