.CHM File Extension

A .CHM file is a Compiled HTML Help File, created by Microsoft.

Open with Calibre. Available for Linux, Windows, and Mac.

What is a .CHM file?

A .CHM file is a type of file known as a Compiled HTML Help File. It is designed to hold help documentation in a format that combines HTML (the language used to create web pages) with other elements like text, images, and links. These files are particularly useful for providing help and instructions for software applications, and they are formatted to be easily navigable.

The content in a CHM file is compressed, which means it takes up less space on a computer. This compression is done using a method called LZX compression. Originally, these files were commonly used in Windows operating systems to provide built-in help documentation for various programs.

To view or use the contents of a CHM file, you can use several different programs: 1. **Calibre** - This is a versatile e-book management software that can also open and view CHM files. 2. **File Viewer Plus** - Available from the Microsoft Store, this application can open a wide range of file types, including CHM files. 3. **Microsoft HTML Help Executable** - This is a program included with Windows operating systems specifically designed to open CHM files. 4. **G.D.G. Software Chm To Exe** - This tool can convert CHM files into executable files, which can then be opened like any standard application. 5. **Calibre** - Mentioned again for emphasis, as it is a popular choice for handling CHM files among other document and e-book formats.

It's important to note that while CHM files were once very popular, they are not as commonly used today. Many software developers have moved towards providing online help through websites and browser-based help systems. As a result, fewer programs support CHM files, and the technology for these files is not as widely maintained.

Additionally, although CHM files are primarily used for help documentation, they can also contain eBooks. This makes programs like Calibre particularly useful for opening them, as it handles various types of e-book formats.


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