Runs in your browser · files never uploaded

Change an EPUB cover online

Pick an EPUB, pick a new cover image, download the fixed book. You can also correct the title and author shown in your library. No sign-up, no upload, no watermark.

How it works

An EPUB is a ZIP archive with a package file (content.opf) that lists every file in the book. Readers find the cover in one of two ways: EPUB 3 books mark an image with properties="cover-image", and EPUB 2 books use <meta name="cover" content="…">. This tool:

1. Finds the existing cover image using both methods (and falls back to an image named “cover”).
2. Replaces the image bytes. If the format changes (for example JPG → PNG) it renames the file and updates every page that pointed to the old one.
3. If the book has no cover at all, it adds the image, the cover metadata for both EPUB 2 and EPUB 3 readers, and a cover page at the start of the book.
4. Writes the title and author into the Dublin Core metadata (dc:title, dc:creator).
5. Rebuilds the EPUB with the mimetype file first and uncompressed, as the EPUB container spec requires — so Apple Books, Kobo, Calibre and Send to Kindle accept it.

Changing the cover for Kindle, Apple Books and Kobo

Kindle (Send to Kindle)

Edit the cover here, then send the EPUB with Send to Kindle. If the old cover keeps appearing, delete the book from the device and from your Kindle library first — Kindle caches covers by book identity.

Apple Books (iPhone, iPad, Mac)

Apple Books reads the cover from the EPUB metadata. Remove the old copy, then open the edited file with Books. On iPhone, save the file to Files and share it to Books.

Kobo and other e-readers

Copy the edited file over USB. Some readers keep thumbnails in a cache; deleting the old book before copying the new one avoids that.

Doing it in Calibre instead

Calibre can also change covers (Edit metadata → Browse cover), but it is a large desktop install. This page does the same single job in a tab, on any computer, phone or tablet.

Questions

Is my book uploaded?

No. The EPUB is unzipped, edited and zipped again by JavaScript running in this tab. You can disconnect from the internet after the page loads and it still works.

Does it work with DRM-protected books?

No. Encrypted books cannot be edited. It works with DRM-free EPUB files, such as most books from independent stores, Project Gutenberg, Standard Ebooks or files you created yourself.

What image size should I use?

A tall image with a 1:1.6 ratio, around 1600 × 2560 pixels, is a safe choice for most stores and readers. JPEG keeps the file small; PNG is fine for artwork with text.

Will the rest of my book change?

No. Only the cover image, the package file and (when the image format changes) the pages that referenced the old cover file are touched. Text, styles and fonts are copied as they are.