Convert EPUB to FictionBook Online Free

Convert EPUB ebooks to FictionBook FB2 format for reading in FBReader, CoolReader, and the wider Russian ebook ecosystem. Powered by Calibre.

Quick Answer

ChangeThisFile converts your EPUB ebook to the FictionBook FB2 format using Calibre on our secure servers. FB2 is an open XML-based format widely used across Russian-language e-reader apps like FBReader and CoolReader. Chapter structure, metadata, and cover art are preserved. Your file is encrypted in transit and auto-deleted after conversion, free with no signup.

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Convert EPUB to FictionBook

Drop your EPUB file here to convert it instantly

Drag & drop your .epub file here, or click to browse

Convert to FictionBook instantly

EPUB vs FictionBook: Format Comparison

Key differences between the two formats

FeatureEPUBFictionBook (FB2)
DeveloperIDPF/W3COpen XML community standard
StructureZIP container of XHTML/CSS filesSingle XML file with all content inline
StylingFull CSS support, embedded fontsBasic inline styles, limited CSS
MetadataOPF manifest with rich metadataRich metadata in XML header (title, author, genre)
Reader supportUniversal (Kobo, Apple Books, most e-readers)FBReader, CoolReader, popular in Russia/Eastern Europe
DRMOptional DRM (Adobe, Apple)No DRM support
File sizeCompressed XHTML (typically small)Single XML file (moderate, uncompressed)

When to Convert

Common scenarios where this conversion is useful

Read in FBReader or CoolReader

FBReader and CoolReader are among the most popular e-reader apps in Russia and Eastern Europe, and natively support FB2. Converting your EPUB library to FB2 gives you access to these readers' advanced typography and customization features.

Russian ebook ecosystem compatibility

Many Russian online bookstores and ebook libraries distribute content in FB2 format. Converting your EPUB purchases to FB2 lets you integrate them with locally downloaded titles in a unified library.

Single-file portability

Unlike EPUB's ZIP container, an FB2 file is a single XML document. This makes FB2 easier to manage in file systems, email, and chat apps without worrying about archive integrity.

Library normalization

If your reading workflow centers on FBReader's metadata-rich library view, converting all ebooks to FB2 ensures consistent author, genre, and series tagging across your entire collection.

How to Convert EPUB to FictionBook

  1. 1

    Upload your EPUB file

    Drag and drop your .epub file onto the converter, or click to browse. Files up to 50 MB are supported for free.

  2. 2

    Server-side conversion

    Your file is securely uploaded to our servers where Calibre converts the EPUB's XHTML content into FictionBook XML, preserving chapters, metadata, and embedded images.

  3. 3

    Download the result

    Once conversion is complete, click Download to save your .fb2 file. Your uploaded file is automatically deleted from our servers.

Frequently Asked Questions

FictionBook is an open XML-based ebook format where the entire book — text, metadata, and images — is stored in a single .fb2 file. It is especially popular in Russia and Eastern Europe and is natively supported by apps like FBReader and CoolReader.

Yes, completely free. Convert EPUB to FictionBook with no cost, no signup, and no watermarks.

Yes. Calibre maps EPUB's XHTML chapter files to FictionBook's section elements, preserving headings, paragraph structure, and the table of contents.

Yes. Calibre embeds cover images and inline images as Base64-encoded binary objects within the FB2 XML. No image data is lost during conversion.

Yes. EPUB's OPF metadata fields — including title, author, publisher, language, and series — are mapped to the corresponding FB2 header elements by Calibre.

Yes. EPUB footnotes are converted to FictionBook note sections, which FBReader and CoolReader display as tap-to-view popup notes.

No. FictionBook has limited font-embedding support compared to EPUB. Your e-reader app's default fonts will be used. Font choices set in the EPUB may not carry over.

No. Files are automatically deleted immediately after conversion completes. Nothing is retained or logged.

No. DRM-protected ebooks cannot be processed. Only DRM-free EPUB files are supported for conversion.

Files up to 50 MB are supported for free conversion. Most EPUB ebooks are well under this limit.

The conversion uses Calibre, the open-source ebook management tool, running on our secure servers to ensure reliable and accurate output.

Currently, files are converted one at a time. Upload your next file after downloading the result.

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