Text Compare
Free online text comparison tool. Compare two texts side by side, find differences with word-by-word diff highlighting. No registration required.
Why Use Our Text Compare Tool?
Our text comparison tool makes it easy to find differences between two texts instantly. Whether you're comparing document revisions, code changes, or validating data, our word-by-word diff algorithm highlights additions in green and removals in red for clear visual feedback. All processing happens in your browser — your data never leaves your device.
Key Features
- Word-by-word diff using LCS algorithm for precise comparison
- Color-coded highlights: green for additions, red for removals
- Switch sides button to swap Text A and Text B
- Copy diff results with markup notation
- 100% client-side processing — your data stays private
How to Use This Tool
- Paste or type your first text in the Text A field
- Paste or type your second text in the Text B field
- Click 'Find Difference' to run the comparison
- Review the highlighted diff and copy results if needed
Technical Details
This tool uses the Longest Common Subsequence (LCS) algorithm to compute an optimal word-by-word diff. The LCS approach finds the longest sequence of words common to both texts, then marks the remaining words as added or removed. This produces a minimal, intuitive diff that highlights only the actual changes between two texts.
Frequently Asked Questions
Is my text sent to a server?
No. All text comparison happens entirely in your browser using JavaScript. Your data is never uploaded to any server.
How accurate is the diff algorithm?
Our tool uses the LCS (Longest Common Subsequence) algorithm, which produces mathematically optimal word-level diffs that highlight only the actual changes.
Can I compare very long texts?
Yes, the tool handles texts of any length. However, very large texts (over 100,000 words) may take a few seconds to process due to the O(n*m) complexity of the LCS algorithm.
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