Free MOBI to EPUB Converter

Worked example

Drop Short Stories.azw3, a DRM-free book of about 4 MB. The page reads it at once. "Title" shows Short Stories, "Author" shows M. Okoye and "Language" shows English. The cover appears beside them, and the line under the boxes reads "14 parts · 9 pictures · KF8 (AZW3)". Press "Convert to EPUB and download". The button reads "Converting…", Short Stories.epub is saved, and the page says "Done: an EPUB with 14 chapters and 8 pictures." The count is one lower than the summary because the cover is one of the 9 pictures in the file but is not placed in the text; it is used as the EPUB cover instead. A note then says to open the file in Apple Books, Kobo or Google Play Books, or email it to your Kindle with Send to Kindle.

Which settings to use, and the limits

• Check Title, Author and Language before you convert. The boxes are filled from the book's own metadata. For the title, a book without one falls back to the full name in the file header, and then to the short name stored at the start of the file, with underscores shown as spaces. "Language" is set only when the book names one the picker offers; otherwise it shows English, so change it for a book in another language. Readers use it for hyphenation, and right-to-left languages such as Arabic, Persian and Hebrew make the book read right-to-left. The saved file is named after the Title box, with characters that file names cannot hold turned into spaces.
• Know which files it opens. The drop zone takes .mobi, .azw3, .azw, .prc and .pdb files, one book at a time, up to 200 MB. It reads old MOBI 6 books and KF8 (AZW3) books, and when a .mobi also holds a KF8 copy, that copy is used. The whole file is read into memory when you add it. The line under the boxes ends with "KF8 (AZW3)" or "MOBI" to show which kind it found. Only books without DRM can be converted, and a note at the foot of the page says so.
• Read the summary line. The line under the boxes reads like "14 parts · 9 pictures". Parts are the sections the book itself separates with page breaks; pictures are every JPEG, PNG or GIF image stored in the file, the cover included. After converting, the "Done" message counts the chapters in the EPUB and only the pictures placed in the text, so it can show fewer pictures than the summary. The chapter count can also differ from the parts count, because of the next tip.
• Chapters follow the book's page breaks and headings. Each part becomes a chapter named after its first short line (80 characters or fewer), or "Chapter 3" and so on when that line is longer. If the book has at least two Heading 1 lines, chapters start at those lines instead; failing that, at Heading 2 lines when there are at least two. There is no setting for the split. Tables of contents are rebuilt from the chapters under the heading "Contents", with Heading 2 lines inside a chapter listed beneath it.
• Expect clean text, not the Kindle layout. Text, headings, lists, tables, block quotes, bold, italics, underline, superscript, subscript and web or e-mail links are kept, and the book is rebuilt with one plain stylesheet. The book's own fonts, colours and page design are not carried over. Publisher and description in the file are read but not written to the EPUB. If the book names a cover picture, it is shown beside the boxes ("Book cover"), becomes the EPUB cover and cannot be changed here. Only JPEG, PNG and GIF pictures are packed, and only the ones the text actually uses.
• Press once, then open the file. "Convert to EPUB and download" builds the book and saves it in one step, and your original file is not changed. If you edit Title, Author or Language afterwards, the "Done" message is cleared; press the button again to save a new copy. Open the EPUB in Apple Books, Kobo or Google Play Books, or use Send to Kindle. The book is converted in your browser; the file is read on your device and not uploaded.

Common problems and how to fix them

It says "This book is DRM-protected (encrypted for one Kindle account), so it cannot be converted. Read it in the Kindle app, or look for a DRM-free copy."

The book's header marks its text as encrypted. Books bought from the Kindle Store are usually protected like this. The tool does not decrypt anything, so there is nothing to change in its settings. Read the book in the Kindle app, or find a copy of the same title that has no DRM and add that file instead.

It says "This book uses a Kindle compression (HUFF/CDIC) this converter cannot read yet. Most of these books are also DRM-protected."

The book's text is stored with HUFF/CDIC compression. This tool reads only books that are uncompressed or use the common PalmDOC compression, so it stops at the header. Look for another copy of the book in .mobi or .azw3 form. If the book came from a store, it is probably also DRM-protected, and the DRM message above applies.

It says "This is not a MOBI, AZW3 or PRC e-book. Check the file, or try the PDF to EPUB or Word to EPUB converters."

The file is not a Kindle or Palm e-book. It may be a PDF, a Word file or another format that was renamed or picked by mistake. Use PDF to EPUB or Word to EPUB for those. A Kindle Topaz book (.azw1) is not in the accepted list, so it gets "File type not supported" and its name; one renamed to .azw gets "This is a Kindle Topaz book (.azw1), a scanned-page format that cannot be converted to EPUB."

It says "The file looks damaged or incomplete. Try downloading it again."

The book's internal table of sections points outside the file, which usually means a download was cut short, or the file uses a compression type the tool does not know. Any unexpected error while reading also ends here. Download or copy the file again and compare its size with the original. The separate message "This file is over 200 MB, too large to convert in a browser." is about size, not damage.

It says "The EPUB could not be created. Try again, or on a computer if you are on a phone."

The book was read, but building or zipping the EPUB failed. The whole book, its pictures and the new archive are held in memory at once, so a picture-heavy book is more likely to fail on a phone, which is why the message suggests a computer. Press "Convert to EPUB and download" again, then try a computer. Any failure in this step shows the same message.

How it compares

This tool reads Kindle books without DRM (.mobi, .azw, .azw3, .prc, .pdb) and writes a reflowable EPUB 3, with chapters, pictures, cover, title and author. It converts one book at a time, up to 200 MB, and only the title, author and language can be edited. It does not remove DRM, and it cannot open HUFF/CDIC-compressed or Topaz books. The output uses a plain stylesheet, so the book's own fonts, colours and page design are not kept. A desktop e-book program gives control over metadata, styling and the chapter list that this page does not offer. In exchange, nothing needs installing, and the book is converted in your browser and not uploaded.