FictionBook (FB2) stores a whole book as structured XML, which makes it easy to convert but rare outside Russian-language readers.
Common Uses
Fiction books
Russian eBooks
XML-based reading
FB2 Conversion FAQ
What is an FB2 ebook file?
+
FB2 is an open ebook format. The file is essentially a zipped collection of HTML pages, CSS, and embedded images, which means most reader apps and devices can open FB2 without conversion. An FB2 is a single XML file with the entire book, its metadata and its base64-embedded images inline.
Why does the same FB2 book look different on two devices?
+
Because it is meant to. An FB2 is a package of structured text and styling that the reader lays out at your chosen font and size, so page count and line breaks are properties of the device, not of the book. Converting to a fixed-layout format freezes one particular rendering — good for printing, worse for reading on a phone. FB2 is FictionBook, an XML ebook format created in Russia around 2004 and still dominant in Russian-language libraries.
Who uses FB2 in practice?
+
Digital libraries and archives, largely — the format is XML-based, so a book in it is structured data rather than a rendering, and it can be validated, indexed and transformed programmatically. That is a serious advantage for a collection and irrelevant to a single reader, whose device probably wants something more common. FB2’s single-file XML structure is trivially machine-readable and carries far richer bibliographic metadata than EPUB.
What if my FB2 is a scan rather than real text?
+
Then nothing downstream can read it until OCR has run. A scanned page is a picture of words: it looks fine, and searching, copying or converting to an editable document all come back empty. Optical character recognition adds a real text layer over the image, after which the words are selectable and the conversion produces an actual document instead of a wrapper around a photograph.
Does an FB2 have fixed pages?
+
No — content flows, and pages appear only when something decides on a page size. Change the font, the margins or the screen and the page numbering changes with it. That is why a page reference from an FB2 is unreliable, and why converting to a fixed-layout format is the step that makes page numbers mean something.
Who controls the FB2 format?
+
Nobody, and that is the point of it. The specification is public, anyone may implement it without asking or paying, and no company can change the terms later — which is why archives, standards bodies and public institutions specify formats like this one for anything that still has to open in twenty years. The trade is not compatibility, which is excellent; it is that there is no vendor to call when some tool implements the spec badly.
Can I convert a whole folder of FB2 files in one go?
+
Yes — drop them in together and they are queued as one job rather than converted one at a time, with the same settings applied across the batch and the results returned together. Free accounts run a couple concurrently; a paid plan lifts both the concurrency and the per-file size limit, which is what makes converting a large archive practical.
Why convert FB2 to another ebook format?
+
Convert FB2 to EPUB for the widest non-Kindle reader support (Apple Books, Kobo, Google Play Books). Convert FB2 to MOBI or AZW3 to read on older Kindles and Kindle Fire. Convert to PDF when you need a fixed-layout copy for printing. FB2 is barely supported outside Russian-language readers, and Kindle and Kobo hardware ignore it entirely.
Does MP4.to remove DRM from FB2?
+
No. MP4.to converts unencrypted FB2 files only. DRM removal is a legal grey area in many jurisdictions and we do not ship that capability.
Are images preserved when converting FB2?
+
Yes — covers, illustrations and embedded photos in your FB2 file are carried over to the output. If the target format compresses images differently (PDF, EPUB), you may see a small size change.
