Add your FB2 file
Drop one or more .fb2 files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
Converting a .fb2 ebook to .epub carries the book's reading-order content into a different package. Free, private, and validated — the file never leaves your browser.
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.Converting a .fb2 ebook to .epub carries the book's reading-order content into a different package. FictionBook 2.0, written to disk as .fb2, is an XML ebook format that describes a book's structure — chapters, epigraphs, poems, citations — rather than its visual appearance. Because everything including images lives in one XML document, an .fb2 file is easy to parse, validate, and transform.
EPUB is the open, vendor-neutral standard for reflowable ebooks, and the .epub extension marks a book whose text rewraps to fit any screen size or font preference. Under the hood an .epub file is an ordinary ZIP archive holding XHTML chapters, stylesheets, images, and a manifest that tells the reading app what to display in what order. For this route the practical draw is reflows to fit any screen, font size, or orientation and open, royalty-free specification with no vendor lock-in — balanced against kindle devices cannot open a sideloaded .epub directly; Amazon converts it during Send-to-Kindle delivery, which is worth knowing before you commit a large batch.
The practical trigger for this conversion is usually a mismatch: with .fb2, base64-encoded images inflate the uncompressed size by roughly a third. Switching to .epub buys you reflows to fit any screen, font size, or orientation, which is why it is the better fit for distributing self-published novels through stores like Kobo, Apple Books, and Google Play. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
| Aspect | FictionBook ebook (.fb2) | EPUB ebook (.epub) |
|---|---|---|
| Format type | Text-based — characters and structure, so there is no visual quality loss | Text-based — characters and structure, so there is no visual quality loss |
| How it stores data | a single well-formed XML file; binary resources such as cover art are embedded as base64 inside binary elements | a ZIP container whose first entry must be an uncompressed file named mimetype identifying the archive as an EPUB |
| Strongest at | ebook distribution in Russia and Eastern Europe, where it is a native store format | distributing self-published novels through stores like Kobo, Apple Books, and Google Play |
| Weak spot | base64-encoded images inflate the uncompressed size by roughly a third | kindle devices cannot open a sideloaded .epub directly; Amazon converts it during Send-to-Kindle delivery |
| Metadata | a mandatory description block records title, authors, genres, language, translator, and publishing history in structured XML — richer than most rival ebook formats | the OPF package embeds Dublin Core metadata — title, creator, language, identifier, publisher, and date — alongside a declared cover image; tools such as Calibre extend it with series and rating fields |
Drop one or more .fb2 files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
Select .epub in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if EPUB is selectable, the route is real and validated.
Press Convert. The book package is parsed in your browser in spine order; DRM-free files only, and nothing is uploaded.
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid EPUB file. Outputs keep the original filename with the .epub extension.
There is no visual quality to lose — fb2 is text-oriented and epub is text-oriented, so the question is structural fidelity. Text, ordering, and basic structure are preserved; complex layout, embedded objects, and styling beyond the target's model are simplified.
Yes — the .fb2 file is processed inside your browser tab and never uploaded. The book package is parsed in your browser in spine order; DRM-free files only, and nothing is uploaded. Close the tab and the file is gone from memory.
Virtually every reading system outside Amazon opens EPUB natively, including Kobo, Apple Books, Google Play Books, and open-source apps such as Calibre and Thorium. Amazon has accepted EPUB uploads through Send-to-Kindle since 2022, though the file is converted to a Kindle-internal format on delivery rather than rendered as-is.
It depends on the content: a ZIP container whose first entry must be an uncompressed file named mimetype identifying the archive as an EPUB. Convert one representative file first and compare before batch-processing a large set.
In .fb2, a mandatory description block records title, authors, genres, language, translator, and publishing history in structured XML — richer than most rival ebook formats. Re-encoding through the browser pipeline does not carry embedded metadata into the output, which doubles as a privacy scrub — check the exported file if you specifically need tags preserved.