How does text comparison work?

The diff tool analyzes two texts line by line and highlights differences: additions in green, deletions in red, and changes in yellow. Perfect for code review and document comparison.

Can I compare source code?

Yes, the diff tool works with any type of text including source code, documents, configurations, and more. It shows exact differences between two versions.

Is it free and private?

Yes, the diff tool is 100% free. All processing happens in your browser, your texts are never sent to any server.

Text Diff / Compare Tool

Compare two texts side by side with highlighted differences for free. Find additions, deletions & changes instantly. Perfect for code review & document comparison.

Processing: local in your browser

Original Text1 lines

Modified Text1 lines

Ignore whitespace

All comparison is done in your browser. No data is sent to any server.

Free Online Text Diff & Compare Tool

Compare two texts side by side with color-coded differences. Find additions, deletions, and changes instantly. Perfect for code review, legal document comparison, version control, and translation verification.

How Diff Comparison Works

Our comparator uses the Longest Common Subsequence (LCS) algorithm to precisely identify differences between two texts. It supports line-by-line and word-by-word comparison. Additions are highlighted in green, deletions in red, and modifications are clearly marked for quick, error-free identification.

Common Use Cases

Code review: compare old and new versions of your code before committing. Legal documents: verify changes between contract versions. Translations: compare original text with translation to detect omissions. SEO: compare meta descriptions or content between page versions.

Local Processing

All processing happens in your browser using pure JavaScript. The texts you compare are never sent to ToolsFree. This avoids an upload to our server, while device and browser security still matter for sensitive documents.

Frequently Asked Questions

How does text comparison work?: The diff tool analyzes two texts line by line and highlights differences: additions in green, deletions in red, and changes in yellow. Perfect for code review and document comparison.
Can I compare source code?: Yes, the diff tool works with any type of text including source code, documents, configurations, and more. It shows exact differences between two versions.
Is it free and private?: Yes, the diff tool is 100% free. All processing happens in your browser, your texts are never sent to any server.

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