Diff Checker
Compare two versions of a text and see exactly which lines were added, removed or left unchanged, highlighted line by line.
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How to use diff checker
- 1Paste the original text on the left.
- 2Paste the modified text on the right.
- 3Review the highlighted diff below — green for added lines, red for removed.
About this tool
This tool computes a line-level diff — it compares the two texts line by line and finds the smallest set of additions and removals that explains the difference between them, the same general approach used by version control tools like Git when showing you what changed in a commit.
A line that was edited shows up as one removed line (the old version) followed by one added line (the new version), rather than trying to highlight the specific characters that changed within the line — this keeps the comparison simple and unambiguous for any kind of text, not just code.
Frequently asked questions
No — this is a line-level diff. A changed line shows as the old line removed and the new line added, rather than highlighting individual words or characters within it. This keeps behavior consistent for any text, not just source code.
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