Click the "Select File" button above, and choose your HHK file.
You’ll see a preview, if available.
Click the "Convert file to..." button to extract text information.
Convert HHK to another file type
To convert HHK index files to another format, you need HTML Help Workshop or other Developer software.
Convert a file to HHK
To convert other file formats to the "Help Project File" file type, you need software like HTML Help Workshop or a similar tool.
About HHK files
The .HHK file is an HTML Help Index file created by Microsoft HTML Help Workshop. It contains a hierarchical list of index keywords used to navigate compiled Windows Help (CHM) files. Under the hood, this format is typically written in plain text using basic HTML lists combined with proprietary sitemap objects. This format has major disadvantages for general users. It is part of an aging, Windows-centric documentation system that is largely unsupported on modern web browsers, macOS, or mobile devices. Furthermore, opening an .HHK file directly provides little value without the accompanying help project files, as it only contains the index terms, not the actual article text. The best conversion targets for an .HHK file are standard HTML or plain TXT files. Converting it allows you to read and extract the keyword index without requiring specialized legacy authoring tools. However, converting it away from its original structure breaks the link to the compiled help project. This file format is difficult to process automatically because it relies on specific Microsoft object classes embedded within HTML tags. Standard online converters often fail to parse the index hierarchy correctly. Just drag and drop your file onto convert.guru to see what it is and convert it if supported. Our analysis tools can inspect the underlying text structure to help you view the raw content and extract the data safely.
Convert.Guru analyzes your HHK file, detects the exact format, and lets you read the text inside.
If you want to convert HHK file to SYS, DLL, EXE, DRV, VXD, 386, COM, BAT, CMD, SCR, PIF or LNK, you can use HTML Help Workshop or similar software from the "Help System Keyword Indexing" category. In the File menu, look for Save As… or Export….
To convert MSI, EXE, REG, MST, LNK, CAB, CAT, DRV, INF, SYS, MSU or DLL files to HHK, try HTML Help Workshop or another comparable tool in the "Help System Keyword Indexing" category.
The HHK 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 HHK converter.