FB2 to RST Converter
FileFlip converts FB2 to RST entirely inside your browser, using Pandoc compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert an FB2 file to RST?#
- Drop your FB2 file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to RST and the conversion starts on its own. FileFlip downloads 65.8 MB of WebAssembly the first time and nothing after that, then runs Pandoc on your own machine.
- Save the RST file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting FB2 to RST lose quality?#
Not in the sense of pixels or samples. Converting FB2 to RST rebuilds the file in RST's own model rather than re-encoding it, so everything RST can represent comes through exactly and anything it cannot has to be dropped. Expect the words to come through exactly and the page breaks to move.
Is it safe to convert FB2 files online?#
Yes, because nothing is uploaded. FileFlip converts FB2 files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What FB2 to RST actually does to the file#
Converting FB2 to RST runs on Pandoc, downloads 65.8 MB of WebAssembly the first time and nothing after that, rebuilds the file in the target's own model, keeps selectable text and page layout.
| Engine | Pandoc |
|---|---|
| Conversion path | One step: FB2 → RST |
| Downloaded to your browser | 65.8 MB, once, then cached by your browser |
| Quality | Rebuilt in the target's model |
| You get back | One file |
| Where it runs | In a background worker, so the page stays responsive |
What survives the conversion
| What is in the file | This conversion | Why |
|---|---|---|
| Selectable text | Kept | Carried through into the converted file. |
| Page layout | Kept | Carried through into the converted file. |
What is an FB2 file?#
An FB2 file is a single XML document that holds an entire book's text, metadata and base64-encoded cover images, in the FictionBook format that originated in the Russian-language ebook scene.
Keep a book as FB2 when it is sourced from a Russian-language ebook library and the reader is FB2-native, such as FBReader or a PocketBook device.
Convert FB2 to EPUB to read the book on a device or app outside the small set of readers that understand FictionBook directly.
What is an RST file?#
An RST file holds reStructuredText, the markup David Goodger designed in 2001 for Python documentation, where directives and interpreted text roles extend the syntax with cross-references, footnotes and generated content that Markdown has no built-in equivalent for.
Write in reStructuredText for Python documentation or any Sphinx-built site that needs directives, cross-references and generated indexes.
Convert reStructuredText to Markdown when the destination lives outside the Sphinx or Python ecosystem, since most directives don't have a Markdown equivalent.
FB2 to RST questions people ask#
Can I open an FB2 file on a Kindle?
Not directly. Kindle devices do not read FB2, so the file needs converting to EPUB or MOBI first, either through Amazon's Send to Kindle pipeline or a separate converter.
What is an FB2 file?
An FB2 file is an ebook in the FictionBook format, a single XML document that holds the full text, metadata and any cover image in one file rather than the zipped archive EPUB uses. It was created in 2004 and is most common in Russian-language ebook collections.
What reader apps open FB2 files?
FBReader, Calibre, Okular and SumatraPDF all read FB2 files natively, and it is also the default format on many e-readers sold in Russian-language markets. Mainstream apps like Apple Books and the Kindle app do not.
What is reStructuredText used for?
reStructuredText is the markup behind Python's own documentation and most Sphinx-built documentation sites, chosen because PEP 287 made it the standard format for Python docstrings. Its directive system lets a project define custom content types, which is why documentation with heavy cross-referencing tends to land on it over Markdown.