3Pub Assist software (v1.2) for ePub2 to ePub3 conversion.

Available for OSX(Mac) and Windows

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The software converts ePub2 files to an ePub3 directory (ie an unzipped ePub3 file), including features such as Guides, nested TOC, Javascript includes and some entries which are not supported in ePub3 (the software converts them to CSS styles). ReadAloud overlays are not currently supported.


The package includes both Windows and Mac versions in the .zip and has been tested on Windows8 and OSX 10.9.2 (Mavericks), but should work on Windows XP, Win7, Win8, OSX 10.7, 10.8 and 10.9. If you have problems with the software, please contact me.

About the software



The original ePub2 file should have passed an ePub check, such as is available (freely) from pagina.

You should then check the resulting ePub3 directory and if all OK, edit any files as required (and check again!)


Note, that  the ePub checker will create an ePub file for you (if there are no warnings or errors).


3Pub Assist is free to use, but you can also make a donation when purchasing.

If you choose not to donate, the required payment details will not be required.


You may not distribute the software to others:-)


If you have trouble converting your ePub2 file, I will be happy to consider modifying the code, but you will need to email me the ePub2 file for testing purposes.