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Text Diff Tool

Compare two blocks of text and see every addition, deletion, and change — highlighted line by line.

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Free Online Text Diff Tool

Compare two texts instantly and see exactly what changed. Our diff tool highlights additions (green), deletions (red), and unchanged lines — making it easy to review changes in code, documents, configs, or any text content.

How It Works

The tool uses the Longest Common Subsequence (LCS) algorithm to find the optimal alignment between your two texts, then highlights the differences line by line. Everything runs in your browser — no data leaves your device.

Use Cases

Features

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Frequently Asked Questions

How do I compare two text files online?

Paste the first text into the left panel and the second into the right panel. The diff tool instantly highlights additions in green and deletions in red. No file upload required — everything runs in your browser securely.

What is a text diff tool used for?

Text diff tools compare two versions of text and show exactly what changed. Developers use it for code reviews, writers use it for document revisions, and teams use it to track changes before publishing or deploying.

Can I use this to compare code files?

Yes, the text diff tool works perfectly with code. Paste two versions of your script or config file and see the exact lines that differ. Great for reviewing changes before committing to git.

Does text diff work with large documents?

Yes, the tool handles large texts efficiently. Comparison runs in your browser so there are no server-side file size restrictions. Very large files may take a moment to process.

Is my text kept private?

Completely private. All comparison happens client-side in your browser. No text is ever sent to a server, making it safe for confidential documents and private code.