EPUB Metadata Editor
Client-side · No upload · No account
A book that shows up as “Unknown Author” or “untitled” on your shelf, or the one with the wrong cover, is usually a three-field fix. Drop the EPUB in, correct what is wrong, and download the file. Chapters, fonts and styles are copied through untouched.
Drop an EPUB here
Edit the title, authors, cover and description, then download the fixed file. The book never leaves your browser.
Where readers get the shelf wrong
Title and author come from the file, not the filename. Every EPUB carries a package document with dc:title and dc:creator fields, and that is what a reader displays. A file called Pride-and-Prejudice.epubwhose metadata says “Untitled” shows as Untitled, everywhere, until the field is fixed.
The cover is just another image in the archive. The package points at it, and readers show whatever it points at. Replacing that image is enough; no reader needs anything re-converted. This editor also resizes what you give it to 1600 px, so a phone photo of a paperback becomes a cover that loads instantly.
Sort order follows the author field. A shelf sorted by author puts “Austen, Jane” and “Jane Austen” in different places. Making every book by an author use the same spelling is the fix, and this is the quickest place to do it. In GemReader's library the corrected file imports with its new title and cover the first time.
Questions
Is the book uploaded anywhere?
No. The EPUB is opened with JavaScript in your tab, the package document is edited in memory, and the new file is assembled on your device. You can disconnect from the network after the page loads and it still works.
What exactly does it change inside the EPUB?
Only the package document (the .opf file) and, if you replace it, the cover image. Every other entry — chapters, styles, fonts, images — is copied byte-for-byte from the original, so the text is untouched and the file re-packs in seconds even for a 150 MB textbook.
Will the new cover show up in my reader?
It replaces the image the book already points at, so any reader that showed the old cover shows the new one. If the book had no cover at all, one is added and flagged both the EPUB 2 way (meta name="cover") and the EPUB 3 way (properties="cover-image") so old and new readers both find it.
Why not just use Calibre?
Calibre is excellent and does far more than this. It also needs a desktop, an install, and a library import before you can edit one field. This page fixes a title or cover on a phone in under a minute, and writes nothing else into the file — no calibre:* metadata, no re-converted markup.
Does it work on DRM-protected EPUBs?
The metadata can be edited, because the package document is never encrypted, but the book still will not open in any third-party reader. Check first with the DRM checker so you do not spend time fixing a cover on a file you cannot read.
My EPUB is valid but the editor says it is not an EPUB.
The most common cause is a file that was renamed from .zip or .cbz — those are archives with no META-INF/container.xml. The second is a damaged download, where the ZIP directory at the end of the file is missing. Re-download and try again.