How do I compare two text files online?

Paste the original text in the left panel and the modified text in the right panel, then click Compare. Differences are highlighted with green for additions and red for deletions.

What algorithm does the diff checker use?

The diff checker uses a line-by-line comparison algorithm similar to the Unix diff command, detecting the minimal set of changes between two texts.

Can I compare code files with the diff checker?

Yes, the text diff checker works for any plain text including code, configuration files, markdown, and logs.

Does the diff checker ignore whitespace?

You can toggle the "Ignore whitespace" option to compare only meaningful content changes without flagging indentation differences.

How do I see a side-by-side comparison?

The diff checker shows side-by-side view by default with the original on the left and modified on the right, with differences highlighted in both panels.

Text Diff Checker – Dev Tools Online — Free Developer Utilities

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Quick Answer

A text diff checker compares two versions of a document and highlights exactly what changed — additions are shown in green, deletions in red. Paste your original and modified text into both panels and click Compare to see a precise line-by-line difference report.

Paste two texts to compare them. Additions and deletions are highlighted inline.

Original Text

Modified Text

Diff Output

Added Removed

Cite This Tool

Text Diff Checker. (2026). DevTools Online. Retrieved from https://devutilitypro.com/text-diff-checker/

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