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HomeDeveloper ToolsDiff Checker

Diff Checker — Compare Two Texts Side by Side

Compare two texts side by side with highlighted differences.

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How to Use

  1. 1Paste the original (older) version of your text into the left panel.
  2. 2Paste the modified (newer) version into the right panel.
  3. 3Click Compare to run the line-by-line comparison.
  4. 4Review the highlighted output: green lines were added in the modified version, red lines were removed from the original. Unchanged lines appear without color.
  5. 5Scroll through both panels to trace where each change was made in context.
  6. 6Click Clear to reset both panels and start a new comparison.

About Diff Checker

The Diff Checker compares two blocks of text and highlights differences line by line. Added lines are shown in green, removed lines in red, making it easy to spot every change at a glance.

Developers use it to compare code versions, review pull request changes, and verify configuration file diffs. Writers and editors use it to track document revisions, compare draft versions, and audit content changes before publishing.

All comparison runs locally in your browser. No text is transmitted to any server — safe for comparing proprietary code, confidential documents, and sensitive configuration files.

Frequently Asked Questions

How does the comparison work?

The tool compares texts line by line, identifying lines that were added, removed, or unchanged.

Can it compare code?

Yes, it works with any plain text including source code, configuration files, and markup.

Is there a size limit?

There is no hard limit, but very large texts may take a moment to process.

Does it show word-level differences?

The tool compares at the line level. Lines with changes are highlighted as a whole. For character-level diffs within a line, compare shorter sections.

Is my text sent to a server?

No. All comparison runs locally in your browser. Your text never leaves your device — safe for comparing proprietary code and confidential documents.

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