HLB Converter

Extract text from VMS help libraries (HLB)


Drop or upload your .HLB file
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How to extract text from your HLB file

  1. Click the "Select File" button above, and choose your HLB file.
  2. You’ll see a preview, if available.
  3. Click the "Convert file to..." button to extract text information.

Convert HLB to another file type

To convert HLB help libraries to another format, you need OpenVMS or other System software.

Convert a file to HLB

To convert other file formats to the "Help Library File" file type, you need software like OpenVMS or a similar tool.


About HLB files

The .HLB file extension represents a VMS / VAX Help Library. Originally developed by the Digital Equipment Corporation for the OpenVMS operating system, these files store hierarchical system documentation and user manuals for mainframe environments. The format is highly proprietary and obsolete for standard modern computing. The biggest disadvantage is that .HLB files are locked to the OpenVMS help utility. You cannot double-click them on modern operating systems like Windows, macOS, or Linux. They lack support for modern web browsers and require either a running OpenVMS environment or specialized legacy parsing tools to extract the text cleanly. Users usually need to convert .HLB files to standard text formats like TXT, MD, or PDF to archive the documentation or migrate it to modern knowledge bases. However, converting this format is notoriously difficult because standard online converters fail to process the VMS-specific control characters and hierarchical index structures. Because it is a closed, proprietary format, often only the original system software can properly read or export the data. If our analysis detects plain text or embedded document structures, viewing or partial conversion may still be possible.

Convert.Guru analyzes your HLB file, detects the exact format, and lets you read the text inside.


FAQ

If you want to convert HLB file to , you can use OpenVMS or similar software from the "System Documentation Storage" category. In the File menu, look for Save As… or Export….

To convert files to HLB, try OpenVMS or another comparable tool in the "System Documentation Storage" category.



The HLB 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 HLB converter.