What is an FB2 file?

What FB2 is

FB2 is a plain-text format you can open in any editor. It is used for handing a finished file over.

The extension is .fb2, and the full name is FictionBook 2. Both matter less than what the file can hold, which is what the rest of this page is about.

Where FB2 came from

It dates from 2004.

Age is worth knowing here for one practical reason: the older a format is, the more programs have had time to learn it.

The specification is public

Anyone can implement it without asking permission or paying a licence, which is why it turns up in so many programs and why files written twenty years ago still open.

It is a specialist format

It exists to do one job well for one group of people. Outside that job it is a poor default, and inside it there is usually nothing better.

It can hold several pages in one file

A FB2 file is not limited to one page, which matters when converting to something that is: a target that holds one image produces one file per page, and the numbering it chooses is worth checking before you send it on.

What opens FB2

Calibre and FBReader read it, and so do most programs of the same kind.

If a file will not open, the format is rarely the problem — it is more often that the program predates it. Converting to something older is the reliable way past that, and it is what the rest of this site is for.

Opening it in a browser

No browser reads it.

That is the single most common reason to convert it: not that the format is bad, but that the place you want to show the file cannot read it.

It is a working format

FB2 is meant to be opened and changed. Keep the file in this format for as long as the work is going on, and export from it whenever a finished copy is needed.

The facts, in one place

Converting FB2 to something else

• FB2 to PDF

Formats worth considering instead of FB2

• Electronic Publication
• Portable Document Format