Compare two texts line by line and see exactly which lines were added, deleted or left unchanged, with line numbers and a downloadable diff.
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When two versions of a document, list, config file or piece of code need to be checked against each other, reading both by eye is slow and error-prone. This tool compares them the way diff tools do: it finds the longest run of lines the two texts share, in order, and reports everything else as added or deleted.
Because order matters, a reordered line or a line that was added twice is not hidden, which a simple 'which lines appear in both' check would miss. Counts and line numbers tell you at a glance how big the change is and where it is.
This text comparison tool shows exactly what changed between two versions of a text. Paste the original into Text A and the changed version into Text B, and it lines them up and marks every added line with + and every deleted line with −, with line numbers from both texts, counts for added, deleted and unchanged lines, and a unified diff you can copy or download. Lines are compared in order, so moved lines and repeated lines show up as changes. Everything runs in your browser.
Add the first text in one box and the second text in the other box.
The tool lines the two texts up in order and finds what was added and deleted. Optionally ignore whitespace, case or blank lines.
Read the + (only in Text B) and − (only in Text A) lines, with line numbers and a summary count.
Copy the result or download it as a unified diff file.
Put the original in Text A and the changed version in Text B. The comparison updates as you type.
Check the added, deleted and unchanged counts. 'The texts are identical' appears when nothing differs.
Lines marked + exist only in Text B and lines marked − exist only in Text A. Long unchanged parts are folded away, and you can show everything instead.
Turn on Ignore whitespace, Ignore case or Ignore blank lines when spacing or capitalization changes don't matter.
Copy diff or Download diff gives a standard unified diff with context lines, built from exactly what is on screen.
Best For
Input
Text A: "Introduction / The price is $10. / Conclusion / Thanks". Text B: "Introduction / The price is $12. / Conclusion / Thanks".Output
− The price is $10. + The price is $12. (3 lines unchanged, 1 added, 1 deleted)The edited line appears as a deletion followed by an addition at the same place, with the line numbers of both texts, and the surrounding lines are marked unchanged.
If the summary says the texts are identical, every line matches in order.
Paste both versions and read the + and − lines to see exactly what was added and deleted.
Download or copy the unified diff to attach to a ticket, email or code review.
Problem
Solution
Order matters. A line moved elsewhere is shown as deleted in one place and added in the other.
Problem
Solution
Changes are shown per line. A line that differs by one word appears as a whole line deleted and a whole line added; there is no word-level highlighting.
Problem
Solution
'Total' and 'total', or a line with an extra space, are different lines until you turn on Ignore case or Ignore whitespace.
Problem
Solution
The comparison works on up to 8,000 lines or 1,000,000 characters per side. Beyond that you are asked to compare a smaller part.
Ignore whitespace and Ignore blank lines make re-indented or re-spaced text compare as identical.
Swap A and B turns additions into deletions and the other way round.
The downloaded .diff uses the standard format (--- / +++ / @@ hunks), which review tools and editors understand.
Windows (CRLF), Unix (LF) and old Mac (CR) line endings compare as equal, and one final newline is not counted as a difference.
The tool compares whole lines. There is no highlighting of the changed words or characters inside a line, no syntax highlighting and no three-way merge.
Up to 8,000 lines or 1,000,000 characters per text. Two texts that share many of the same lines in a completely different order (for example the same lines reversed) can also be refused for line-by-line comparison, with a message, to keep your browser responsive.
The tool shows and exports a diff. It cannot apply a patch, compare folders or files directly, or keep a history of versions.
When two lines differ only in spacing or capitalization and you chose to ignore that, they count as unchanged and Text A's version is displayed.
Both compare line by line in order; they differ in how much detail they show.
| This tool | A code-editor or IDE diff | |
|---|---|---|
| Comparison | Ordered line-by-line diff with line numbers and counts | Ordered diff, usually with word-level and syntax highlighting |
| Output | Copy or download a standard unified diff | Often a side-by-side view and patch tools |
| Where it runs | In your browser, nothing uploaded | In your editor or a hosted service |
Which should you use?
Use this tool for a quick, private check of what changed between two texts. Use an editor's diff when you need word-level highlighting or to merge changes.
The most common questions are whether this is a real diff and whether it shows modified lines. It is a real line-by-line diff in order; a changed line is shown as the old line deleted and the new line added. The FAQ below covers the options, the size limits and what the diff file contains.
It is a real line-by-line diff. The two texts are lined up in order, lines marked + exist only in Text B, lines marked − exist only in Text A, and unchanged lines are shown in between, with line numbers from both texts.
As a deleted line followed by an added line at the same place. There is no word-level highlighting inside the line.
Yes. Lines are compared in order, so a line moved to a different place is shown as deleted and added, and a line repeated three times in one text and once in the other shows two deletions.
They change how lines are compared, never the text itself. Ignore whitespace treats lines that differ only by spaces or tabs at the ends or repeated inside as equal; Ignore case treats Total and total as equal; Ignore blank lines skips empty lines. Equal lines are shown as they appear in Text A.
Yes. Copy diff and Download diff give a standard unified diff (--- / +++ headers and @@ hunks with three lines of context), built from the same comparison you see on screen.
Up to 8,000 lines or 1,000,000 characters per text. Larger input is not compared, and you are told why, so the page never freezes. Texts that share many lines in a completely different order (such as the same lines reversed) can also be refused.
No. CRLF, LF and CR line endings compare as equal, and a single newline at the end of a text is not counted as an extra line.
No. CoditTools compares your text entirely in your browser using JavaScript. Nothing is sent to a server.
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