CHM (Compiled HTML Help) files are a popular format for software documentation, help files, and even some ebooks. While Windows has built-in support for CHM, you may want more features or the ability to read these files on other platforms. This guide covers the top free CHM readers and online tools to help you access CHM content with ease.
What are CHM Files?
CHM files contain compressed HTML pages, images, and scripts bundled into a single file. Microsoft introduced this format in 1997 as a replacement for the older WinHelp system. CHM files are still widely used for software manuals and technical documentation.
Best Free CHM Reader Software
1. Calibre
Calibre is a powerful, open-source ebook management tool that also serves as an excellent CHM reader.
Key Features:
- Supports a wide range of ebook formats, including CHM.
- Offers a built-in ebook viewer with customizable fonts, colors, and layouts.
- Includes tools for ebook conversion, allowing you to convert CHM to other formats.
- Provides library management features for organizing your ebook collection.
How to Use Calibre to Read CHM Files:
Step 1: Download and install Calibre from the official website.
Step 2: Launch Calibre and click the “Add books” button on the toolbar.
Step 3: Browse to your CHM file and select it to add to your Calibre library.
Step 4: Double-click the added CHM file in your library to open it in Calibre’s built-in viewer.
Calibre’s versatility makes it an excellent choice for managing and reading not just CHM files, but a variety of ebook formats.
2. Sumatra PDF
Despite its name, Sumatra PDF is a lightweight, multi-format document viewer that supports CHM files.
Key Features:
- Fast and lightweight application with a minimalist interface.
- Supports multiple document formats including PDF, EPUB, MOBI, and CHM.
- Offers basic navigation and viewing options like zoom, rotation, and full-screen mode.
- Available as a portable application, no installation required.
Using Sumatra PDF for CHM Files:
Step 1: Download Sumatra PDF from the official website.
Step 2: Install the application or extract the portable version to a folder.
Step 3: Right-click on a CHM file and select “Open with” > “Sumatra PDF” to view the content.
Sumatra PDF’s simplicity and speed make it an excellent choice for quickly viewing CHM files without the need for a more complex application.
3. Cool Reader
Cool Reader is an open-source, cross-platform ebook reader that supports CHM along with various other formats.
Key Features:
- Customizable reading interface with various themes and font options.
- Text-to-speech functionality for supported languages.
- Bookmarking and annotation features.
- Support for multiple ebook formats including EPUB, FB2, DOC, and CHM.
Reading CHM Files with Cool Reader:
Step 1: Download and install Cool Reader from the project’s SourceForge page.
Step 2: Launch Cool Reader and use the “File” > “Open” menu to browse to your CHM file.
Step 3: Select the CHM file to open it in the reader.
Step 4: Use the toolbar or menu options to customize your reading experience, such as adjusting font size or enabling night mode.
Cool Reader’s cross-platform nature and extensive customization options make it a versatile choice for reading CHM files across different devices.
Online CHM Readers
1. GroupDocs Viewer
GroupDocs Viewer is a web-based document viewer that supports CHM files along with many other formats.
Key Features:
- No software installation required – works directly in your web browser.
- Supports viewing CHM files without downloading them to your device.
- Offers options to download viewed CHM content as PDF or images.
- Provides a clean, responsive interface for easy reading on various devices.
Using GroupDocs Viewer for CHM Files:
Step 1: Visit the GroupDocs Viewer website.
Step 2: Click on the “Choose File” button and select your CHM file.
Step 3: Wait for the file to upload and process. The CHM content will then be displayed in your browser.
Step 4: Use the viewer’s interface to navigate through the CHM content, zoom in/out, or download the file in other formats if needed.
GroupDocs Viewer is an excellent option when you need to quickly view a CHM file without installing any software, especially on devices where you can’t install applications.
2. CHM Reader (Chrome Extension)
For Chrome users, the CHM Reader extension offers a convenient way to view CHM files directly in the browser.
Key Features:
- Integrates seamlessly with Google Chrome.
- Allows viewing of CHM files stored locally on your computer.
- Provides a familiar browser-based interface for navigating CHM content.
- Supports search functionality within CHM files.
Setting Up CHM Reader in Chrome:
Step 1: Open the Chrome Web Store and search for “CHM Reader”.
Step 2: Click “Add to Chrome” to install the extension.
Step 3: Once installed, click on the extension icon and select “Choose File” to open a CHM file from your computer.
Step 4: The CHM file will open in a new tab, allowing you to browse its contents using the extension’s interface.
This extension is particularly useful for Chrome users who frequently need to reference CHM files and prefer keeping their workflow within the browser.
Whether you prefer a dedicated application or a web-based solution, these free tools provide various options for reading CHM files. Each option has its strengths, so consider your specific needs when choosing. For frequent CHM readers, Calibre or Sumatra PDF might be the best choices due to their robust features and offline capabilities. For occasional use or when you’re on a device where you can’t install software, online tools like GroupDocs Viewer can be incredibly handy. Happy reading!