Click the "Select File" button above, and choose your ULZ file.
You’ll see a preview, if available.
Click the "Convert file to..." button to extract text information.
Convert ULZ to another file type
To convert ULZ Lists to another format, you need 7-Zip or other Compressed software.
Convert a file to ULZ
To convert other file formats to the "Software Update Archive" file type, you need software like 7-Zip or a similar tool.
About ULZ files
A .ULZ file primarily functions as a compressed Windows or Office update list used by the WHDownloader (formerly Windows Updates Downloader) tool. These files store large lists of available operating system updates in a compressed archive to save bandwidth. Because the internal format is often standard ZIP, users can extract them using archiving software like 7-Zip to view the underlying XML data. Less commonly, .ULZ files serve as mobile device firmware updates created by LG Electronics, containing Microsoft Compound data, or as USBlyzer Data Capture Files. Users typically need to convert or extract .ULZ files because the default format is unreadable without specific downloader tools or firmware flashing software. The main disadvantage of the .ULZ format is its highly specialized nature; it is not supported by web browsers, standard text editors, or default operating system viewers. For update lists, the best conversion target is ZIP or XML, allowing you to read the text data. For firmware or USB capture data, extraction might yield BIN files, though the raw proprietary structure remains difficult to read. Because these files use obscure extensions for internal binary or compressed structures, standard online converters fail to process them. Just drag and drop your file to identify the format, view it, and convert it when possible using convert.guru.
Convert.Guru analyzes your ULZ file, detects the exact format, and lets you read the text inside.
If you want to convert ULZ file to CSV, JSON, XML, YAML, YML, TOML, INI, CFG, CONF, DAT, DB or SQL, you can use 7-Zip or similar software from the "Update List Archiving" category. In the File menu, look for Save As… or Export….
To convert DBF, XML, SQLITE, XLSX, SQL, TSV, ACCDB, YAML, MDB, CSV, ODS or JSON files to ULZ, try 7-Zip or another comparable tool in the "Update List Archiving" category.
The ULZ Converter Story
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 ULZ converter.