PDFSwift › EPUB tools › EPUB Merge
📚 EPUBFree · runs in your browserMerge Multiple EPUB Files Into One Book
Combine two to twenty EPUB books into one EPUB 3 file. Each book keeps its own folder and table of contents, and a combined contents page lists them in the order you choose.
Drop two or more EPUB files here
or choose files from your device
What this tool does
People merge EPUBs to bind a series into one file, to collect articles saved as separate books, or to put course readings in a single download. The challenge is that every EPUB has its own package file, identifiers and navigation, so concatenating archives does not work.
This tool builds a new package. Every book’s files are copied into their own folder inside the new archive (book1/, book2/, …) so their internal links keep working without rewriting. The new manifest lists all resources with prefixed ids, the spine places the books one after another, and a fresh navigation document and NCX give a top-level entry per book, with each book’s own chapters nested beneath.
The result is an EPUB 3 file with a new identifier, the title you enter, the combined list of authors and the language of the first book. EPUB 2 documents are brought up to the EPUB 3 doctype. Books with encrypted resources are refused, because their fonts depend on an identifier that would change.
How to use this tool
- Choose two or more EPUB files, or drop them on the page. They are listed in the order they were added.
- Use the arrows to reorder and the × to remove a book. At least two books are required; up to 20 are accepted.
- Enter the title for the merged book. A title made from the book titles is suggested.
- Press Merge EPUB files. The tool builds the book and validates the result.
- Press Download merged EPUB. Your original files are not modified.
Supported formats and limitations
- Input: two to twenty EPUB 2 or EPUB 3 files, 100 MB each.
- Output: one EPUB 3 file.
- Kept: chapters, images, styles, fonts, each book’s internal links and table of contents.
- New: package identifier, modification date, combined navigation and NCX.
- Not supported: books with
encryption.xml, books that cannot be read (repair them first). Series metadata and individual covers are not merged. - Input: EPUB 2 and EPUB 3 files (
.epub), up to 100 MB. Anything else is rejected before processing. - Archive safety: files with unsafe paths (such as
../), duplicate entries, more than 8,000 entries or an expanded size above 500 MB are refused. - Not supported: DRM-protected books and books with encrypted or font-obfuscated resources (
META-INF/encryption.xml) can be opened for inspection but cannot be converted or merged. - Memory: the whole book is held in your browser’s memory. Very large illustrated books may fail on a phone; a desktop browser has far more headroom.
Privacy and safety
This tool runs entirely in your browser. When you choose a file it is read by JavaScript on this page; it is not uploaded to PDFSwift or to any other server, and the result is created on your device and handed to you as a download. Closing or reloading the tab discards the book from memory.
The page shows advertising supplied by a third party. Advertising scripts run separately from the tool and never receive your book. If you prefer, you can disconnect from the internet after the page has loaded and the tool will still work.
Frequently asked questions
How do I merge EPUB files?
Add the books, put them in order, enter a title and press Merge EPUB files. Download the combined book.
Will the table of contents work?
Yes. The merged book has a top-level entry for each book with its own chapters beneath it.
What happens to covers and metadata?
The merged book gets the title you enter, a combined list of authors and the language of the first book. It has no cover until you add one with the cover editor.
Are the files uploaded?
No. The books are combined in your browser.
Why was one of my books refused?
Either it contains encrypted or font-obfuscated resources, or it has no readable package. Run the validator or repair tool for the latter.
Can I merge EPUB 2 and EPUB 3 books?
Yes. The output is EPUB 3 and the older content documents are converted to the HTML5 doctype.
Is there a limit on the number of books?
Up to 20 at a time, each up to 100 MB, and the total depends on your device’s memory.