What does the diff algorithm compare?

Lines are compared first (line-level diff), then within changed lines, words are compared to show finer-grained changes highlighted in darker colors.

Yes. The diff checker works on any plain text including source code. Paste old and new versions of a function, config file, or document.

Is my text stored anywhere?

No. All comparison happens in your browser using JavaScript. Your text never leaves your device.

What do the colors mean?

Green lines/words are additions (present in new but not old). Red lines/words are deletions (present in old but not new). Unchanged lines are shown in neutral color.

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Text Diff Checker

Compare two text blocks and highlight additions, deletions, and changes — line-by-line diff with word-level highlighting.

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About this tool

Side-by-side text comparison tool. Paste two versions of a text and see every difference highlighted: added lines in green, removed lines in red, and changed words highlighted within lines. Useful for comparing code snippets, documents, or any two pieces of text.

How to use

1 Paste the original text in the left panel.
2 Paste the modified text in the right panel.
3 Differences appear highlighted automatically — green for additions, red for deletions.
4 Use the stats bar to see how many lines were added, removed, or changed.

Frequently Asked Questions

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