10 Best File Comparison and Difference (Diff) Tools in Linux

When programmers or writers work on files they sometimes need to see the differences between two versions of the same file or between two separate files. This process of finding the differences is called “diffing.” On Linux systems, there is a command called ” diff ” that compares files and shows you what has changed. This command displays the differences between the files in a way that is easy to understand. There are many tools available on Linux that help you compare files and see the differences. Some of these tools work in the terminal, while others have a graphical user interface (GUI) that makes it easier to visualize the changes.

In this guide, we will look at some of the best tools for comparing files on Linux. These tools are useful when you are writing code or working with text files, as they make it easy to identify and understand the changes you or others have made.

The ‘diff’ tool is a command-line utility that comes with Linux and is used for comparing two files and displaying the differences between them. It’s a simple and easy-to-use tool that compares files line by line and highlights the lines that are different.

Command :

diff file1.txt file2.txt 

Output :

This command will compare the contents of ‘file1.txt’ and ‘file2.txt’ and show the lines that are not the same between the two files.

‘vimdiff’ is a command-line tool similar to ‘diff’, but it offers more advanced features. It allows you to view and edit up to four files simultaneously while highlighting the differences between them. ‘vimdiff’ opens the files in the Vim text editor, which means you need to have Vim installed on your system to use this tool.

Command :

sudo apt install vim (On Ubuntu and similar)

To compare the three or four files simultaneously just run the below command.

Command :

vimdiff file1.txt file2.txt file3.txt

Output :

‘vimdiff’ will open the specified files in the Vim text editor, with the differences between the files highlighted. You can navigate through the files and make changes as needed. The output will be the modified files themselves, which you can save or discard as desired.

The ‘sdiff’ tool is a command-line utility that compares two files and displays the differences between them in a side-by-side format. It provides an easy-to-read view of the changes, with added lines marked with ‘>’ and removed lines marked with ‘<‘. Lines that are the same in both files are shown without any special markings.

Command :

sudo apt install diffutils  (On Ubuntu and similar)

sudo yum install diffutils  (On RedHat and similar)

To compare the two files simultaneously just run the below command.

Command :

sdiff file1.txt file2.txt

Output :

This will show you the differences between the two files side-by-side. Now let’s look at some graphical diff tools you can use on Linux instead of these command-line tools.

Kompare is a graphical file comparison tool that allows you to visually compare files and see the differences between them. Unlike the command-line tools, Kompare provides a user-friendly interface that can make it easier to understand and merge changes. To install Kompare on your Linux system, you can run one of the below command.

Command :

sudo apt install kompare (On Ubuntu and similar)

After installing Kompare, you can launch the application from the menu or by running the kompare command in the terminal.

Command :

kompare 

Output :

DiffMerge is a cross-platform graphical tool that allows you to visually compare and merge changes between files or entire directories. It provides two main functionalities diffing and merging. To install DiffMerge on Ubuntu and similar distributions, you can use the following command.

Command :

sudo apt install diffmerge

After installing DiffMerge, you can launch the application from the menu or by running the diffmerge command in the terminal. For other Linux distributions, you can download the appropriate installer from the official DiffMerge.

Link : https://sourcegear.com/diffmerge/downloads.php

Meld is a lightweight graphical tool designed specifically for developers and programmers to compare files, folders, and code versions side by side. It offers various features to make the comparison and merging process more efficient and visually clear. To install Meld on Ubuntu and similar distributions use the below command.

Command :

sudo apt install meld (On Ubuntu and similar)

After installing Meld, you can launch the application from the menu or by running the meld command in the terminal.

Command :

meld

Output :

Diffuse is a free graphical tool for comparing and merging files on Linux systems. It is written in Python and provides two main functionalities: file comparison and version control integration. To install Diffuse on Ubuntu and similar distributions use the below command.

Command :

sudo apt install diffuse (On Ubuntu and similar)

After installing Diffuse, you can launch the application from the menu or by running the diffuse command in the terminal.

Command :

diffuse

Output :

XXdiff is a free and powerful tool for comparing and merging files and directories on Linux and other Unix-like systems. It offers advanced visual diffing and three-way merge capabilities but does not support Unicode files or direct editing of diffs. For example, on Ubuntu and similar distributions you can use the below command.

Command :

sudo apt install xxdiff (On Ubuntu and similar)

After installing XXdiff, you can launch the application from the menu or by running the xxdiff command in the terminal. XXdiff provides a graphical user interface.

Command :

xxdiff file1.txt file2.txt

Output :

KDiff3 is a cross-platform graphical tool that enables you to compare and merge files and directories. It works on Linux, macOS, Windows, and other Unix-like systems, making it a versatile choice for developers and writers working across different platforms. To install KDiff3 on Ubuntu and similar distributions use the below command.

Command :

sudo apt install kdiff3  (On Ubuntu and similar)

After installing KDiff3, you can launch the application from the menu or by running the kdiff3 command in the terminal. KDiff3 provides a user-friendly graphical interface,

Command :

kdiff3

Output :

TkDiff is a cross-platform graphical tool that provides a user-friendly interface for comparing two files side by side. It acts as a wrapper for the standard Unix ‘diff’ command but displays the differences in a visual and easy-to-understand way. TkDiff works on Linux, Windows, and macOS, making it a convenient tool for comparing files across different systems. To install TkDiff on Ubuntu and similar distributions use the below command.

Command :

sudo apt install tkdiff  (On Ubuntu and similar)

After installing TkDiff, you can launch the application from the menu or by running the tkdiff command in the terminal. TkDiff provides a graphical user interface.

Command :

tkdiff

Output :

Linux provides various command-line and graphical tools for comparing files and visualizing differences. Command-line utilities like diff and sdiff are simple but text-based. GUI tools like Meld, Kompare, and DiffMerge offer visual diffs with additional features for merging changes and working with code. The right tool depends on your needs and preferences for simplicity or advanced functionality.

What is a diff tool, and why is it useful?

A diff tool compares two files or directories and shows the differences between them. It’s useful for tracking changes made by multiple people or over time.

Can I use diff tools to compare and merge code changes?

Yes, diff tools are commonly used by developers to compare and merge code changes. Many tools integrate with version control systems like Git.

Do I need to use the command line to compare files with diff tools?

No, there are many graphical user interface (GUI) diff tools available, providing a user-friendly visual experience.

Can diff tools handle large files or directories?

Yes, most modern diff tools can compare and merge large files and entire directory structures.

Are diff tools only useful for text files, or can they work with other file types?

While primarily for text files, some diff tools can also handle binary formats like images and executables to a limited extent.