Missing cover guide

Send to Kindle has no cover: what to check

If an EPUB has a cover in Calibre or Apple Books but becomes a grey document after Send to Kindle, the image may be present while the package metadata that identifies it is incomplete.

An EPUB is not one document. It is a ZIP-based container holding HTML, XML, styles and images. The package document—usually an OPF file—tells reading systems which image is the cover. A tolerant reader may infer the cover from the first page or a familiar filename. A conversion service may rely on explicit declarations instead.

The three parts of a working EPUB cover

1. The image must exist

The OPF manifest can point to a file that was renamed, moved or omitted when the book was exported. The path is relative to the OPF file and capitalization can matter. A cover declaration is not useful if the referenced image is absent.

2. The image type must match

The manifest assigns every resource a media type such as image/jpeg or image/png. The declaration should agree with the actual file. The EPUB specification treats these media types as part of the resource contract.

3. The package should identify the cover

EPUB 3 uses the cover-image property on the image’s manifest item. The current W3C EPUB specification recommends this property when a publication includes a cover image. Older EPUB 2 workflows commonly use a metadata element whose content points to the cover item ID. Including consistent declarations helps compatibility across different conversion paths.

Why re-sending the same filename may not help

Kindle library entries can retain an earlier thumbnail. If a repaired file arrives as a duplicate of the old personal document, you may still see the old grey tile. Remove the earlier document from your library, allow the change to sync, and then upload the repaired copy.

A safe troubleshooting order

1. Confirm the EPUB is DRM-free and that you are allowed to modify it.
2. Check whether the archive contains a real cover image.
3. Verify that the OPF manifest points to that exact file with the correct media type.
4. Check both the EPUB 3 cover property and the EPUB 2 compatibility metadata.
5. Rebuild the EPUB container and reopen the output before sending it.
6. Remove the old Kindle library copy before testing the repaired file.

What FixMyEPUB changes

FixMyEPUB performs these checks in your browser. When it finds an existing image with incomplete declarations, it normalizes the EPUB 2 and EPUB 3 metadata, corrects the image media type when it can be inferred safely, rebuilds the container and checks the new file again. If there is no safe image candidate, it asks you to choose a JPG or PNG rather than guessing.

Sources

• W3C EPUB 3.3 specification
• Amazon Send to Kindle