COVERimage + metadata
Find the grey-cover cause
We verify that the artwork exists and that EPUB 2 and EPUB 3 both identify it correctly.
A tiny repair shop for Kindle readers
Fix Send to Kindle
cover & EPUB errors.
Diagnose grey covers and format problems that make Send to Kindle reject your book. Safe fixes happen entirely in your browser.
100% browser-based
0 files uploaded
2 focused checks
The problem, made visible
From grey document
to a real book cover.
FixMyEPUB repairs the EPUB declarations that tell conversion services which image is the cover, then verifies the rebuilt file before download.
Check my cover metadataBeforeGeneric grey document
AfterCover correctly identified
Illustrative result. Amazon conversion, device firmware and cached thumbnails can still affect the final display.
Recognize this screen?
Your EPUB uploads—then Send to Kindle says “Failed.”
This is the other common Send to Kindle failure: the EPUB opens elsewhere, but its package or references do not pass the web uploader’s delivery checks.
See why EPUBs get rejected
Private EPUB check
Check the file behind the cover.
Choose an EPUB to diagnose its cover metadata and the format issues most likely to block Send to Kindle delivery.
1Choose EPUB
2Diagnose
3Download
Drop your EPUB here
or from your device
Checks cover + delivery format · DRM-free EPUB · Under 100 MBReading the package
Inspecting your EPUB…
Looking for the cover image and its metadata.
Diagnosis complete
We found the cover.
No usable cover image found
Add a JPG or PNG and we’ll wire it into the EPUB correctly.
✓
Repair complete
Your repaired EPUB is ready.
The cover metadata has been repaired in a new copy. Your original file was not changed.
◆ Your ebook never leaves this browser.
“
It has a cover in Calibre—but Kindle shows a grey tile, or rejects the file completely.
Those are the two problems we check.Diagnose my EPUB →
Why it happens
A readable EPUB can still fail Kindle’s checks.
An EPUB is a package of XML, HTML and image files. Reading apps often forgive small structural mistakes; Amazon’s conversion system may hide the cover or reject the package instead.
DELIVERYpackage + resources
Find rejection blockers
We check the container, required metadata, manifest targets, spine references and XML resources.
REPAIRrebuild + recheck
Download a verified copy
Safe fixes are written to a separate EPUB and checked again before the download is offered.
A focused diagnostic
We check the EPUB.
We don’t blame the reader.
Every result explains what was found, what can be safely changed, and when the problem is probably outside the EPUB.
Run a private Send to Kindle check →✓
Embedded artworkIs a cover image actually present in the archive?
✓
EPUB 2 cover metadataDoes the legacy cover tag point to a real manifest item?
✓
EPUB 3 cover propertyIs the image explicitly marked with cover-image?
✓
File path and media typeDo references, capitalization and image types agree?
✓
Container and package structureIs the EPUB packaged in the form Amazon expects?
✓
Manifest and spine referencesDo declared resources and reading-order items actually exist?
✓
XML readabilityCan the package and content documents be parsed safely?
Send to Kindle help
Fix the problem you can actually see.
Focused troubleshooting guides for missing covers, rejection emails and EPUB package errors.
Missing cover
Send to Kindle has no cover: what to check
Learn why an EPUB can show a cover in Calibre but arrive on Kindle as a grey document.
Read the cover guideDelivery rejected
Why Send to Kindle rejected your EPUB
Trace package, manifest, spine and XML problems behind Amazon’s generic rejection email.
Read the rejection guideEPUB metadata
How EPUB cover metadata works
Understand EPUB 2 and EPUB 3 cover declarations without opening a code editor.
Read the metadata guideBefore you upload
A few honest answers.
Can you guarantee my cover will appear on every Kindle?+
No. We can repair detectable problems inside the EPUB, but Kindle apps, device firmware, download state and Amazon’s conversion service can also affect thumbnails. If your EPUB is already healthy, we’ll tell you instead of making unnecessary changes.
Why did Send to Kindle reject my EPUB?+
Common causes include invalid package XML, a malformed container, missing manifest resources, broken spine references or incorrect ZIP packaging. The diagnostic names the blocker it can prove without guessing.
Do you upload or keep my ebook?+
No. The EPUB is opened and rebuilt locally by your browser. It is not sent to FixMyEPUB or stored on a server.
Will this change the text or formatting?+
The cover repair only changes package metadata and, when necessary, the selected cover resource. It does not rewrite chapters or alter the prose.
Does this remove DRM?+
No. FixMyEPUB is for DRM-free EPUB files you are allowed to modify. Encrypted or DRM-protected books are not supported.
What should I do after downloading the repaired EPUB?+
Remove the old personal document from your Kindle library, then upload the repaired copy through Amazon’s Send to Kindle service. Duplicate copies may retain the old thumbnail.
Reader feedback
What should we fix next?
Tell us what happened with your EPUB or which Kindle problem is still getting in your way. Please do not paste book contents or personal account details.
Feedback is private and used only to improve FixMyEPUB.
Before you send it again