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Text Diff Checker

Compare revisions of text, code or configuration without uploading them. Choose line or word comparisons, control whitespace matching and narrow the report to additions and removals.

Browser-based · No account required · Copy and export

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BUILT FOR THE DETAILS
  1. 01Add your input
  2. 02Inspect & adjust
  3. 03Use your result
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How to use Text Diff Checker

  1. Paste the original and updated versions, or load a text file into each side.
  2. Choose line or word mode and set whitespace and case handling. Enable changes-only output when unchanged entries are distracting.
  3. Compare, read the + and - markers, and copy or download the report. Swap the versions to reverse the comparison.

When to use this tool

Review changes between configuration files, drafts or log excerpts. Choose line comparison for structure or word comparison for prose, and decide whether case or whitespace differences matter.

What the diff markers mean

A plus marks an entry present in the updated text; a minus marks an entry removed from the original. Unchanged entries have a two-space prefix. The comparison uses a longest-common-subsequence algorithm, so repeated lines can have more than one equally valid alignment. Whitespace and case settings change matching, not the text you supplied.

Worked example

Original: alpha, beta
Updated: alpha, gamma
Line comparison:
  alpha
- beta
+ gamma
(The relative order of adjacent removal/addition markers may differ.)

Limits and output checks

This is a readable comparison report, not a unified patch file for git apply. Word mode tokenizes on whitespace. Exact comparison is bounded to 1.6 million token-pair cells and runs in a worker; split very large revisions into sections.

Reference: Text difference concepts.

Frequently asked questions

Can I compare local files?

Yes. Each file loader fills one text field locally. It does not upload files or infer a binary format.

Does ignoring case modify my source?

No. It changes the values used to compare entries. The report retains the supplied text for displayed entries.

Why was a large comparison rejected?

Exact sequence comparison needs memory proportional to both token counts. The cell limit keeps the browser from attempting an excessive allocation.

Text differences or structured data changes?

Load the two text versions and choose the comparison mode. Use the result to review edits; choose JSON Structural Diff when object values matter more than source formatting.

Scope of this workflow

The report is not a unified patch for git apply. Ignoring case changes comparison behavior, not the source text.

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