Extract text from ADU files
To convert your ADU file to another format, you need Addictive Spell Checker or other Text software.
To convert other file formats to the "User Dictionary" file type, you need software like Addictive Spell Checker or a similar tool.
The .ADU file extension identifies a User Dictionary generated by Addictive Spell Checker, a legacy component suite widely used in Delphi and C++Builder applications to provide spell-checking functionality. Unlike the main dictionary (ADM), the ADU file stores custom words that a user has manually "added to dictionary" to prevent them from being flagged as errors in the future.
Because .ADU files are specific to the Addictive Software ecosystem, they are not natively recognized by modern word processors like Microsoft Word or open-source engines like Hunspell. This creates a significant "vendor lock-in" problem: users who have spent years building extensive lists of technical terms, names, or industry-specific jargon within a legacy application cannot easily migrate this valuable data to new software. The file is effectively a proprietary container for a simple word list.
To recover your custom vocabulary, the best approach is converting the .ADU file to a standard TXT (plain text) or generic DIC format. This allows you to open the list in Notepad, copy the terms, or import them directly into modern browsers, Microsoft Office, or other spell-checking tools for archiving and continued use.
Convert.Guru analyzes your ADU file, detects the exact format, and lets you read the text inside.
Users also converted PDF, MP3, DIC and DCT files.
If you want to convert ADU file to MP3, WAV, AAC, FLAC, OGG, WMA, M4A, AIFF, OPUS, ALAC, APE or WV, you can use Addictive Spell Checker or similar software from the "User Custom Dictionary" category. In the File menu, look for Save As… or Export….
To convert MIDI, AAC, TTA, AU, WV, DTS, MID, FLAC, RA, MP3, PCM or WAV files to ADU, try Addictive Spell Checker or another comparable tool in the "User Custom Dictionary" category.
The history of Convert.Guru began over 25 years ago in California with Tom Simondi’s file-format database. A former contributor to Space Shuttle development and a software pioneer of the 1980s, Simondi established a trusted resource for file type analysis that was even referenced by Microsoft Windows XP. Today, we use modern technology to process and convert thousands of file formats while continually improving our ADU converter.