MOBI → EPUB

MOBI to EPUB

MOBI is a Kindle format from 2000 and almost nothing else reads it. EPUB is read by Kobo, Apple Books, Google Play Books, PocketBook, Calibre and every phone. This converts one to the other here, in the page.

No upload· Files are read in this tab and never sent anywhere

Intake

Drop MOBI files here

.mobi, .prc and .azw are all read. A file that is really an AZW3 is detected and read as one.

Output format

EPUB — The open standard. Reflows to any screen, and read by everything except Kindle hardware.

Add a cover page at the frontSome readers show the cover from the metadata alone; others only show it if it is also the first page. Off means the cover is still in the file and still marked as the cover.

How the chapters are rebuilt

A MOBI has no files inside it. The whole book is one long HTML document with page-break markers, so the chapters here are reconstructed from those markers, and the internal links — which MOBI stores as raw byte offsets — are mapped back onto the chapters they land in. A book with headings gets a contents list from them; a book without says so rather than producing an empty one.

What you get

An EPUB 3 package with an EPUB 2 NCX alongside it, so older readers show a contents list too.
Every image, with the cover marked as the cover.
Metadata read from the EXTH block: author, publisher, ISBN, ASIN, subjects, description.
Markup repaired into strict XHTML, which is what makes the result open at all.

Two things this cannot read

Books with DRM. A protected MOBI is detected from its header and refused with an explanation. Nothing here attempts to decrypt anything.
HUFF/CDIC compression. Some Amazon-generated files use a dictionary compression scheme this build does not implement. It is reported by name rather than as a generic failure.

Converting the other way? EPUB to MOBI. Coming from a newer Kindle file? AZW3 to EPUB.