FB2 to Zim Converter
FileFlip converts FB2 to Zim 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 Zim?#
- 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 Zim 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 Zim file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting FB2 to Zim lose quality?#
Not in the sense of pixels or samples. Converting FB2 to Zim rebuilds the file in Zim's own model rather than re-encoding it, so everything Zim 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 Zim actually does to the file#
Converting FB2 to Zim 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 → Zim |
| 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 a Zim file?#
A Zim file holds a page from Zim, a desktop wiki application that keeps a personal note collection as plain text files marked up with Zim's own lightweight wiki syntax.
Keep notes in Zim markup while they're edited inside the Zim desktop wiki, where the plain text files stay easy to back up and version.
Convert Zim pages to Markdown when notes need to move to a different note-taking app or get published somewhere Zim's syntax won't render.
FB2 to Zim questions people ask#
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.
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 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 a .zim file?
A .zim file holds a page's worth of Zim's wiki markup, the syntax the Zim desktop wiki uses for notes. Zim itself actually saves each page as a plain .txt file inside a notebook folder, so a .zim file is what you get once that page has been exported or converted rather than opened straight from a Zim notebook.