Microsoft .chm Help Format

This page contains information on how to create Compiled Help Module (.chm) files for applications that run under Windows. An alternative for Tcl developers is to use a Wikit in local mode as a help system. Tom Krehbiel


Access to chm from tcl: winhelp


TJK: I'm no expert but the following items may be helpful to others. Please add your own comments, tools and links.

  • A description of the file format can be found here [1 ]
  • Abee Chm Maker is a program for making chm-files. It is free and can be downloaded from here [2 ]. It has a simple and comprehensible interface that allow you to make CHM-files (with contents). I tried it on a simple problem, and it worked and seemed to be easy to use.
  • An X-Windows viewer for .chm files can be downloaded from here [5 ]. lexfiend 4 Dec 2005: This and several other *nix-based CHM viewers uses the "CHM lib" library [4 ], not to be confused with Matt Russotto's chmlib that can be found in his "CHM tools" package [3 ].

Comments on .chm files.

DKF: "Isn't it HTML+postprocessing?"

PT: "Yes. MS issue a HTML compiler. You can take a web site and turn it into a chm file quite easily. You have to dig around in MSDN to find the package to download though. It used to be on the Platform SDK disk."

PT: It's called the MS HTML Help 1.4 SDK and you can download it from [6 ] and view the documentation there.


DAG: See also CHMvfs


With NT (?) and earlier, Microsoft's help format was .hlp, rather than .chm. Here [7 ] are products which run under Linux (among other platforms) and understand .hlp's (never-publicly-documented?) format.