RunConvert Logo

FB2 to OTT Converter

The best free online tool to convert FB2 files to OTT in seconds.

How it works

Three simple steps to your new file.

01

Upload

Drag and drop your files or click to select from your device to get started instantly.

02

Select

Choose your desired output format from our extensive list of supported file types.

03

Convert

Click convert and download your newly formatted file. Fast, free, and secure.

What is an FB2 file?

FB2 (FictionBook) is an XML-based e-book format originally developed in Russia by Dmitry Gribov. Unlike ZIP-based containers like EPUB, an FB2 file is a single monolithic XML document where the text is marked up with semantic tags describing the structure (epigraphs, verses, citations) rather than the visual appearance. Binary data, such as cover images or illustrations, are embedded directly within the XML file using Base64 encoding. This structural focus facilitates easy conversion to other formats and precise rendering across different hardware devices.

How to open an FB2 file

Support for FB2 is prevalent in e-reading software but rare in native OS environments. Calibre is the primary tool for opening and converting FB2 files on Windows, macOS, and Linux. For dedicated reading, FBReader and CoolReader are cross-platform applications specifically optimized for parsing the FictionBook XML schema. Android users frequently use Moon+ Reader, while iOS users can utilize TotalReader or KyBook.

  • Full Name:FictionBook 2.0
  • Developed By:Dmitry Gribov
  • Initial Release:2000
  • MIME Type:application/x-fictionbook+xml

What is an OTT file?

An OTT (OpenDocument Text Template) file is a standardized document template defined by the OASIS Open Document Format for Office Applications (ODF) specification (ISO/IEC 26300). Based on XML syntax and encapsulated within a ZIP-compressed container, the format stores styling definitions, page layouts, and manifest files separate from content, allowing users to generate multiple .ODT files with consistent formatting. It supports lossless compression and interoperability across open-source office suites.

How to open an OTT file

Native support is built into ODF-compliant word processors such as LibreOffice Writer and Apache OpenOffice. Microsoft Word opens OTT files via integrated ODF conversion filters. Because the file functions as a template, opening it typically instantiates a new, untitled document (.odt) rather than editing the template file itself, unless specifically opened for editing via the application's file menu.

  • Full Name:OpenDocument Text Template
  • Developed By:OASIS (Organization for the Advancement of Structured Information Standards)
  • Initial Release:2005
  • MIME Type:application/vnd.oasis.opendocument.text-template
Pro Experience

Want to convert large files without a queue or ads?

Upgrade now to unlock the full potential.