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Developer ToolPopular Text Tool

Text Difference Checker

Compare original and changed text with clear line and word-level highlighting—entirely in your browser.

Side-by-side diffWord highlighting100% private

Original Text

The earlier or reference version

Changed Text

The newer version to compare

Comparison updates automatically after typing.

Diff Legend

Green — added content

Red — removed content

Amber — changed line pair

See exactly what changed

Compare drafts, code snippets, configuration, contracts, and copied content. Line-level structure shows where changes occurred while word highlights pinpoint the exact edits.

What is Text Difference Checker?

Text Difference Checker aligns an original passage with a changed version and highlights added, removed, or modified lines. Editors, developers, and support teams can switch between side-by-side and unified output to review revisions without manually scanning two long documents.

How to use Text Difference Checker

  1. 1.Paste the earlier text into the original panel and the revision into the changed panel.
  2. 2.Choose line or word emphasis, whitespace handling, and side-by-side or unified view.
  3. 3.Run the comparison and inspect insertions, deletions, and paired changes.
  4. 4.Copy the result or download a patch-style diff after confirming the correct text order.

Key features

  • ✓Side-by-side alignment places corresponding original and changed lines together.
  • ✓Unified view uses familiar added and removed line markers in one stream.
  • ✓Optional whitespace normalization reduces noise from spacing-only edits.
  • ✓Word-level emphasis makes small changes inside a line easier to locate.
  • ✓Downloadable diff output can be opened in a text editor or review tool.

Common use cases

  • Review wording changes between two policy drafts.
  • Compare generated configuration files before deployment.
  • Find a changed paragraph in revised client copy.
  • Create a patch-style record of edits to a plain-text template.

Frequently asked questions

What is the difference between side-by-side and unified diff?

Side-by-side uses separate columns for each version; unified diff presents removed and added lines in one continuous patch-style view.

Can the checker ignore whitespace changes?

Yes. Whitespace normalization can treat repeated, leading, and trailing spacing as equivalent during matching.

Does a text diff detect moved paragraphs?

A line-based algorithm may show moved material as a removal and an addition rather than a dedicated move operation.

Is compared text uploaded or stored?

The comparison runs locally in the browser and does not require saving the supplied text in an application database.

What does Download Diff create?

It creates a plain-text unified diff that records line removals and additions for later review.

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