OpenAnyFile
Works
Viewing, inspecting and verifying. You get the source with language-aware colouring and line numbers. File details, exact byte size and the detected signature are always shown.
How to open a .fb2 file
You have a FB2 file and nothing on your machine will touch it. Here is what the format actually is, and how to read one in about four seconds without installing anything.
What is a .fb2 file?
FictionBook 2 eBook is a code format developed by Dmitry Gribov and Mikhail Matrosov, first appearing in 2004. It is normally produced by Russian ebook libraries, Calibre.
The entire book is one XML file with semantic markup, and images are base64-encoded inline. There is no zip container, so an FB2 can be read and edited as plain text.
| Full name | FictionBook 2 eBook |
|---|---|
| File category | Code |
| MIME type | application/x-fictionbook+xml |
| Magic bytes (file signature) | 3C 3F 78 6D 6C (<?xml) |
| Developer | Dmitry Gribov and Mikhail Matrosov |
| Introduced | 2004 |
| Usually created by | Russian ebook libraries, Calibre |
| OpenAnyFile engine | syntax highlighter |
| Opens without upload | Yes — parsed locally in your browser |
Open a .fb2 file in your browser
OpenAnyFile routes .fb2 to its syntax highlighter, which highlights the source with language-aware colouring and line numbers.
- Open the OpenAnyFile opener in this browser — nothing to download or sign up for.
- Drag your .fb2 file onto the drop zone, click to browse for it, or paste it with Ctrl+V.
- The extension is detected and the file is handed to the syntax highlighter.
- Your FB2 opens on its own viewer page: the source with language-aware colouring and line numbers.
- Use fullscreen for a closer look, or download the file back out unchanged. Free, and free in the sense that there is no paid tier waiting behind step three.
What you can and cannot do with it here
Does not work
Editing and re-saving. OpenAnyFile is a reader, not an editor — for changes you still need special software or an equivalent.
No upload, and here is why that matters for {E}
Handing a .fb2 file to a random conversion site means handing over a copy you cannot get back. OpenAnyFile parses the file locally instead — the same way special software reads it off your disk, except the reader happens to be a web page. Nothing is transmitted, so there is nothing to leak, log or subpoena. It also means it keeps working with your Wi-Fi switched off.
Frequently asked questions about FB2 files
Can I open a .fb2 file without installing special software?
Yes. OpenAnyFile's syntax highlighter runs in your browser, so you can read a FB2 file with nothing installed. You get the source with language-aware colouring and line numbers. For full editing you still need the original application — this is a viewer, not an editor.
How can I check a file really is a FB2 file?
Look at the first bytes rather than the extension. A genuine FB2 begins with 3C 3F 78 6D 6C (
Is it safe to open a FB2 file online?
With OpenAnyFile, yes, because nothing is uploaded. The file is read locally through your browser's File API and never leaves your device, so there is no server copy to leak, log or retain. That matters most for the kind of file people are least willing to hand to a random converter site.
What is a .fb2 file, exactly?
FictionBook 2 eBook — an application/x-fictionbook+xml format created by Dmitry Gribov and Mikhail Matrosov since 2004. The entire book is one XML file with semantic markup, and images are base64-encoded inline. There is no zip container, so an FB2 can be read and edited as plain text.
Does the same viewer handle formats related to FB2?
Yes — the same engine also opens .html, .xml, .sql, so you can compare related files without switching tools.
Related formats
These open with the same engine, so if you have one of these sitting next to your .fb2 file, it will open too: