Compare two texts line by line and highlight additions, deletions, and unchanged lines locally in your browser.
Calculations happen locally. We do not send your values to our server.
Changing “The meeting is on Monday.” to “The meeting is on Tuesday.” produces one removed line and one added line. Unchanged surrounding lines stay marked as unchanged.
The checker normalizes line endings and uses a longest-common-subsequence comparison to align lines. A changed line appears as a deletion and an addition. Optional settings ignore letter case or leading and trailing spaces when matching lines.
Each input is limited to 20,000 characters and 600 lines to keep comparison responsive. This is a line-by-line text comparison, not a document-formatting, plagiarism, semantic, or word-level checker. Original inputs are not saved or sent by the tool.
Paste the earlier version on the original side and the edited version on the revised side. This is useful for reviewing a short configuration file, a list or a draft where line boundaries matter. The comparison preserves text and displays old and new line numbers so you can locate a change in either source.
A replacement is shown as one removed line and one added line, not as a single changed word. In the examples below, a minus marks text from the original and a plus marks text from the revision; unmarked text matches. If a paragraph is all on one line, a single-word edit can highlight that entire paragraph. Line movement may also appear as removal and addition.
Keep both ignore options off for a strict comparison after line-ending normalization. Ignore case is useful when capitalization is irrelevant; ignoring leading and trailing spaces can help with pasted lists. Neither option removes internal spacing differences. Repeated identical lines can admit several valid alignments, so the displayed alignment is one consistent comparison, not a record of the author’s edit sequence.
| Example | Result |
|---|---|
A
B → A
C | A
− B
+ C |
A → A
B | A
+ B |
A
B → A | A
− B |
Yes. Blank lines and a final newline can create differences. Windows and Unix line endings are normalized so their encoding alone does not count as a change.
Ignore letter case compares lowercase forms. Ignore leading and trailing spaces trims each line for matching. Matched lines display the revised text; ignored changes are not highlighted, and the input fields remain unchanged.
The comparison runs locally and the tool does not upload or store the text. Avoid entering highly sensitive information on a shared or compromised device. Copying places the comparison on your clipboard; sharing sends only the page link.