How to Generate a .mobi Dictionary File for Kindle using Pyglossary and Kindle Previewer

Requirements

1. Install pyglossary 

   pip3 install pyglossary

2. Install Kindle Previewer
   Download Kindle Previewer

   (At the time of writing, Kindle Previewer version 3.88.0 (Windows).)

   

Step 1: Convert Dictionary Data to .mobi Format with Pyglossary

Pyglossary will generate a folder (e.g., mydict.mobi) instead of a .mobi file.
Within this folder, navigate to the OEBPS directory, where you'll find the content.opf file.

Step 2: Preview the content.opf File in Kindle Previewer

1. Open Kindle Previewer and go to File > Open Book (or press Ctrl + O).

2. Select the content.opf file you found in Step 1.

   Note: The preview may take some time to process, depending on the size of your dictionary.

   Tip: To speed up the preview, you can duplicate the content.opf file (e.g., content_min.opf) and remove most .xhtml files from the manifest and spine sections, leaving only one:

   <manifest>
     <item href="style.css" id="style.css" media-type="text/css" />
     <item href="g000002.xhtml" id="g000002.xhtml" media-type="application/xhtml+xml" />
   </manifest>
   <spine>
     <itemref idref="g000002.xhtml" />
   </spine>
   

3. If you encounter errors during preview, check the Conversion Log in Kindle Previewer.
   For example, you may see:

   "Error","E23005: Language not specified in metadata. The dc:Language field is mandatory. Aborting."
   

   This means the content.opf file is missing the dc:Language field value, along with other possible missing fields such as DictionaryInLanguage and DictionaryOutLanguage.

   To resolve this, manually add the missing fields in the content.opf file.

Step 3: Export the .mobi File from Kindle Previewer

Once the preview is complete, go to File > Export in Kindle Previewer.
If it allows you to export as a .mobi file, great! You’re done.

If the export option is unavailable (e.g., due to large file size), proceed to Step 4.

Step 4: (Optional) Use kindlegen.exe

If Kindle Previewer doesn’t allow you to export, you can use the kindlegen.exe tool, which is included with Kindle Previewer.

1. Navigate to the kindlegen.exe location:
   C:\Users\<your_username>\AppData\Local\Amazon\Kindle Previewer 3\lib\fc\bin\

2. Open a Windows Terminal or PowerShell window, and run the following command:

   C:\Users\<your_username>\AppData\Local\Amazon\Kindle Previewer 3\lib\fc\bin\kindlegen.exe .\mydict.mobi\OEBPS\content.opf -o mydict.mobi
   

   (Replace <your_username> with your actual Windows username.)

This should generate the .mobi file for your dictionary.