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Text Diff Checker

Compare original and revised text and highlight what changed.

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How to use Text Diff Checker

  1. 1. Paste the original text on the left and the revised text on the right.
  2. 2. Compare by lines for documents/code or by words for smaller wording changes.
  3. 3. Optionally ignore letter case or whitespace differences, then review additions and removals.
  4. 4. Use Copy Diff if you need a plain-text change summary.

Useful tips

  • • Line mode is usually easier for code, configuration and paragraph-by-paragraph edits.
  • • Word mode is more precise for short prose but does more comparison work, so line mode is better for very large text.
  • • Ignore whitespace is useful when indentation or spacing changed without changing the wording itself.

Frequently asked questions

What do the colours mean?

Green marks content added in the revised text. Red marks content removed from the original text. Uncoloured content matched.

Does Ignore whitespace change my text?

No. It only changes how items are compared. The displayed text still comes from the original or revised input.

Why can a moved line appear as removed and added?

This checker compares sequences rather than trying to infer intent. Moving content can therefore appear as a removal in one position and an addition in another.

Is there a size limit?

The detailed comparison is intentionally bounded to keep the browser responsive. If word mode is too large, switch to line mode or compare a smaller section.

Is my text uploaded?

The comparison runs in your browser. Your pasted text does not need to be sent to Wid9et to calculate the diff.