Convert FB2 to PDF

An FB2 file is a single XML document holding the entire book: the metadata, the text with its chapter structure, and any illustrations encoded as base64 inside the same file. There is no archive and no manifest — open it in a text editor and the whole novel is there, marked up.

It is a regional standard, used overwhelmingly in Russia and the wider Russian-speaking world and rarely outside it. Windows and macOS have no handler, Kindles and Apple Books do not read it, and browsers show the raw markup. That is why most people meet the format exactly once, holding a file that will not open.

FictionBook marks up what things are: a chapter, a subtitle, an epigraph, a poem with its stanzas and lines, a citation. It says nothing about what any of it looks like — no fonts, no margins, no page geometry, no styling of any kind. The reader’s software has always decided all of that.

A PDF is the opposite: every measurement is fixed and recorded. So converting means the tool must invent a page size, a typeface, a type size, margins, and where every break falls, from a source that deliberately expressed none of it. More is decided for you here than in any other e-book conversion, which is why the settings are worth a moment rather than accepting a default.

The literary markup is the format’s distinguishing feature and the part that translates worst. Verse, stanza and line have exact tags in FictionBook; a PDF has styled paragraphs and indentation. The same is true of epigraphs and block citations, which arrive looking approximately right and structurally flattened.

For a novel this is invisible — prose is prose in both formats. For a volume of poetry it is the whole book, and line breaks that were meaningful become line breaks that happen to fall where the measure ran out. Convert one poem, look at it, and decide before committing a collection.

A PDF does not reference fonts by name and hope; it embeds the glyphs it needs. So the conversion has to supply a typeface containing every character in the book, and for a Russian-language text that means full Cyrillic coverage.

When that goes wrong it does not produce an error — it produces empty rectangles, or occasionally the wrong characters entirely, which is why the first page of the output is worth looking at every single time. A book mixing Cyrillic with Latin quotations or transliteration is the case most likely to expose a gap, because a font may cover one script well and the other partially.

The description block at the top of an FB2 carries more than most e-book formats bother with: author separated into given, middle and family names, translator, original language, series and the number within it, a genre from a controlled list, and a record of who produced the file and when.

A PDF can hold a title and an author and little else, so most of that is dropped by the conversion rather than carried. If you are converting a collection and expect to find things again later, note the series and translator somewhere outside the file, or keep the FB2 as the catalogue record. The information is in the source and it is not in the destination.

Files arrive as .fb2.zip or .fbz very often, and that is exactly what it sounds like: the same XML inside a ZIP. Since the format is verbose text with base64 images, compression is dramatic — frequently down to a fifth of the size — and most tools that read FB2 read the zipped form directly.

If a tool refuses one, unzipping first gives the plain .fb2 and loses nothing. There is no difference in content between the two forms, and no decision to make beyond which one the software in front of you accepts.

Images in an FB2 are base64-encoded and sit inside the same file as the text, which is why an illustrated FictionBook is considerably larger than the equivalent EPUB. Base64 adds roughly a third to the size of whatever it encodes, before any of the markup around it.

That matters for the free 25 MB server ceiling more than for anything else. A plain novel is a fraction of a megabyte; an illustrated volume or a scanned-and-marked-up edition is the category that runs into limits, and it is also the category where the images rather than the text dominate the resulting PDF.

Both FB2 and EPUB describe structure rather than appearance, so converting between them is one vocabulary mapped onto another: chapters stay chapters, the table of contents survives, images come across, and the text stays reflowable. It is about as clean as document conversion gets.

The result also opens on far more devices than the FB2 did — every e-reader, every reading application, and Kindle hardware by way of Send to Kindle, which converts it to Amazon’s own format before it arrives. If the reason for converting is that nothing opens the file, EPUB solves that completely and keeps the reader in control of the type size, which a PDF does not.

Three cases. Printing, because no reading application prints a book properly and a paper copy sometimes has to exist. Annotation, because marking up a PDF is universally supported and the marks stay with the file. And handing the book to somebody whose machine has no reading software at all, where PDF needs no explanation.

Outside those, the fixed page is a cost rather than a feature. It freezes the typeface and the size chosen at conversion time, which is precisely what a reader with poor eyesight, a small phone or a strong preference cannot then change — and it is the one thing the original format was designed to leave open.