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Epub Cover Editor

Replace the cover image of an Epub, or add one to a book that has none. The book stays valid: the image is converted to the format the book already declares, so readers and stores keep trusting it. Everything happens in your browser.

Drop your .epub here, or click to choose.
Loaded on your device. Nothing is uploaded.
Your book never leaves your device. Reading the cover and saving the new one both happen entirely in your browser using WebAssembly. Nothing is uploaded.

How it works

Drop an Epub and the tool finds its cover the same way readers do: the manifest's cover-image entry, or the older meta name="cover" pointer. Pick a replacement image and it is converted to the format the book already uses, swapped in under the same filename, and the book is repackaged. Nothing else changes, so internal links, the reading order and your metadata are untouched.

Adding a cover to a book that has none

If the book has no cover at all, the tool creates one properly: the image goes in as cover.jpg and the manifest is wired up for the book's Epub version (properties="cover-image" for Epub 3, meta name="cover" for Epub 2). That is the difference between a cover that shows up in every library app and one that only works in the tool that added it.

Why covers go missing or wrong

Conversions drop covers, library tools swap in low-resolution thumbnails, and some books ship with a JPEG disguised as a PNG, which is exactly the mismatch stores flag as OPF-029. Replacing the cover here keeps the declared format and the actual bytes in agreement. If you also want to fix the title or author while you are at it, the metadata editor is one tab over.