Free Online MOBI to FB2 Converter
Convert MOBI to FB2 online for free.
Drop MOBI files here
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Up to 50 MB per file. Sign up free to convert files up to 100 MB.
Selected files
| File name | Size | Convert to |
|---|
Preparing files
Checking files and selected output formats.
MOBI vs FB2: Side-by-side
Technical comparison of the two formats, useful for deciding which to use, or for confirming what changes during conversion.
| Property | MOBI | FB2 |
|---|---|---|
| Full name | Mobipocket eBook | FictionBook 2 |
| Year introduced | 2000 | 2004 |
| Developer / standard body | Mobipocket / Amazon | FictionBook (open) |
| MIME type | application/x-mobipocket-ebook | application/x-fictionbook+xml |
| File extension | .mobi | .fb2 |
| Compression | PalmDOC compression | XML (typically uncompressed) |
| Color / data depth | N/A | N/A |
| Max dimensions / size | Software-limited | Software-limited |
| Transparency | No | No |
| Animation | No | No |
| Standard / specification | Mobipocket | FictionBook (open) |
| Best for | Older Kindle devices (replaced by AZW3 then KFX) | Russian-speaking ebook community, lightweight ebook archiving |
Frequently asked questions
Can I convert MOBI books to FB2 for my Kindle or Kobo?
Yes. Upload your MOBI ebook and it converts to FB2 with chapter structure, cover art, and formatting preserved. Load the FB2 onto your Kindle, Kobo, Nook, or any eReader that supports the format.
How to convert MOBI to FB2 without losing the table of contents
Chapter navigation, the cover image, and text formatting all carry over during conversion. The FB2 has proper chapter links so you can jump between sections on your eReader just like the original MOBI.
Can I convert multiple MOBI ebooks to FB2 at once?
Yes. Upload a batch of MOBI files and they are all converted to FB2. Each book downloads separately or as a ZIP, so you can convert an entire library in one session.
Does the text still reflow after converting to FB2?
Yes. FB2 keeps text reflowable, so it adapts to any screen size and font setting on your eReader rather than being locked to a fixed page like a PDF.
Which reader is FB2 for?
FB2 is the FictionBook ebook format best for FictionBook readers. Convert your MOBI to FB2 when your eReader or app opens FB2 more reliably, so the whole library works on one device.
What is MOBI?
MOBI is an Amazon ebook format, typically used for older Kindle devices. Converting it to FB2 produces a file that opens on systems without MOBI support.