Diff Viewer Online

What is a Diff Viewer?

A Diff Viewer is a tool that compares two versions of text and highlights the differences between them. It helps identify added, removed, modified, and unchanged lines, making it easier to review changes and detect mistakes.

What is a diff?

A diff (difference) is the result of comparing two versions of a file or document. It shows exactly which lines have been added, removed, or modified between the two versions.

What algorithm does this tool use?

This tool uses the Myers diff algorithm, one of the most widely used algorithms for text comparison. It is also used by Git and many modern version control systems because it efficiently identifies the smallest set of changes between two documents.

Can I compare source code?

Yes. The Diff Viewer works well with JavaScript, TypeScript, Python, Java, C#, Go, PHP, Ruby, Rust, Kotlin, Swift, HTML, CSS, SQL, and many other programming languages because it compares plain text.

Can I compare JSON, XML, or YAML files?

Yes. You can compare structured text formats such as JSON, XML, YAML, CSV, Markdown, INI, configuration files, and many other text-based formats.

Does this tool compare entire files?

The tool compares any text you paste into the two editors. Simply copy the contents of two files into the tool to compare them side by side.

Does it compare line by line or word by word?

This version performs line-by-line comparison. Entire changed lines are highlighted rather than individual words or characters.

Does whitespace affect the comparison?

Yes. Differences in spaces, tabs, indentation, or blank lines are treated as text changes because they can be significant in many programming languages and configuration files.

Can I compare very large documents?

Yes. There is no fixed size limit imposed by the tool. Performance depends primarily on your browser's available memory and your device's hardware.

Can I use this tool for Git reviews?

Yes. The Myers diff algorithm is the same core algorithm used by Git, making this tool useful for reviewing code changes, pull requests, patches, and revisions outside of a Git repository.

Does this tool modify my text?

No. The Diff Viewer only compares your input and highlights the differences. Your original text remains unchanged.

Is my text uploaded to a server?

No. All comparisons happen locally in your browser. Your documents, code, and other content are never uploaded, stored, or shared with any server.

Can I use this tool offline?

Yes. Once the webpage has loaded, all comparisons are performed locally in your browser without requiring an internet connection.

Which file types can I compare?

Any text-based content can be compared, including plain text, source code, JSON, XML, YAML, CSV, SQL, Markdown, HTML, CSS, JavaScript, TypeScript, configuration files, log files, and documentation.

Who should use a Diff Viewer?

This tool is useful for software developers, DevOps engineers, QA testers, technical writers, database administrators, students, editors, researchers, and anyone who needs to compare two versions of text quickly and accurately.

Why use a Diff Viewer?

A Diff Viewer saves time by automatically identifying differences between two versions of text. It helps reduce mistakes during code reviews, document editing, configuration management, debugging, and quality assurance, making it easier to understand exactly what has changed before sharing, deploying, or publishing your work.