Text Diff Checker Online Free — Compare Texts Instantly
Compare two texts side-by-side and highlight differences.
What is Text Diff Checker?
Compares two blocks of text line by line and highlights the differences: added lines (green), removed lines (red), and unchanged lines (grey). Shows a summary of changes at a glance.
Common Use Cases
Comparing document versions, proofreading edited articles, checking API response changes, reviewing code comments, verifying translated text fidelity, and spotting unintended changes.
How It Works
Performs a line-by-line diff using the Myers diff algorithm. Added lines (in text B but not A) are shown in green, removed lines (in A but not B) in red, unchanged lines in grey.
Frequently Asked Questions
Does it do character-level or line-level diff?
Line-level by default, which is clearest for text. Differences within changed lines are highlighted at word level.
Can I compare large documents?
Yes. The diff handles large texts, though very long documents may take a moment to process.
How can I use this to review changes?
Paste the original version in the left field and the new version in the right field. Green shows additions, red shows deletions.
Can I export the diff results?
Copy the highlighted diff directly from the tool. For more advanced needs, use command-line diff tools.
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