How to Compare Two Files in Notepad++

Notepad++ offers several built-in methods for comparing two files, making it a versatile tool for identifying differences between documents, code, or configuration files. This guide will outline the various techniques you can use to efficiently compare files within Notepad++.

Built-in Compare Plugin

Notepad++ includes a powerful “Compare” plugin that provides a side-by-side comparison of two files. This plugin highlights differences in text, making it easy to spot additions, deletions, and modifications.

To use the Compare plugin:

1. Install the Plugin: If the Compare plugin isn’t already installed, navigate to Plugins > Plugins Admin. Search for “Compare” and install it. You may need to restart Notepad++ for the plugin to take effect.
2. Open the Files: Open both files you want to compare in Notepad++.
3. Launch Compare: Go to Plugins > Compare > Compare, or use the keyboard shortcut (typically Alt+D).

Understanding the Comparison View:

• Side-by-Side Display: The two files are displayed side-by-side, allowing for easy visual comparison.
• Highlighted Differences: Differences are highlighted in distinct colors, typically green for additions and red for deletions.
• Navigation: You can navigate between differences using the dedicated navigation buttons in the plugin toolbar.

Using a Third-Party Diff Tool

While Notepad++’s Compare plugin is effective, you can also integrate external diff tools for more advanced comparison features. Notepad++ supports launching external diff tools directly from the application.

To configure an external diff tool:

1. Open Preferences: Go to Settings > Preferences.
2. Navigate to External Tools: Select the “External Tools” tab.
3. Add a New Tool:
   • Command: Enter the path to your preferred diff tool executable.
   • Arguments: Specify the command-line arguments required by your diff tool to compare two files. This typically involves placeholders like $(FULL_CURRENT_PATH) and $(FULL_PATH_TO_FILE) representing the file paths.
   • Save: Save the configuration with a descriptive name (e.g., “Compare with Beyond Compare”).

Using the External Diff Tool:

1. Open the Files: Open the two files in Notepad++.
2. Run the Tool: Go to Plugins > External Tools and select the configured diff tool from the list.

Manually Comparing Files

For simple comparisons or when a dedicated comparison tool isn’t available, you can manually compare files by arranging the Notepad++ windows side-by-side.

To manually compare:

1. Open the Files: Open both files in separate Notepad++ windows.
2. Arrange Windows: Go to Window > Move To Other View to move one file to a separate view group.
3. Tile Vertically: Go to View > Move/Clone Current Document > Move Current Document to Another View and then View > Arrange Vertical/Tile to display the two files side-by-side.

This method relies on visual inspection to identify discrepancies, and might be less efficient for large or complex files. However, it’s a viable option for quick comparisons.

Conclusion

Notepad++ provides multiple methods for comparing files, from its integrated Compare plugin to seamless integration with external diff tools. Choose the method that best suits your needs and complexity of the comparison task. Whether you’re a programmer debugging code, a writer reviewing revisions, or a system administrator managing configurations, Notepad++ offers the tools you need for efficient file comparison.