Text compare
Compare two blocks of text line by line and see exactly what changed.
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About this tool
Paste two versions of anything — a config file, a contract clause, a log, an email thread — and see which lines were added, removed and edited, with the changed words marked inside each edited line. Case, indentation and trailing spaces can be ignored when they are not the point, and mismatched Windows and Unix line endings are called out by name rather than reported as a thousand changes. The result can be copied as a standard unified diff for a pull request or a patch file.
Using this tool
The two texts look identical but every line is marked as changed. Why?
Almost always mismatched line endings — one side came from Windows (CRLF) and the other from macOS or Linux (LF). This tool unifies them before comparing and tells you when they differ, so you get a readable comparison and still learn about the byte-level difference.
What does the similarity percentage mean?
The share of the longer text whose lines matched exactly, after the options you chose. It is a rough orientation figure, not a plagiarism score — two texts can say the same thing in different words and score close to zero.
Can I use the result as a patch?
Yes. “Copy unified diff” produces the standard format that git apply and the patch command accept, with three lines of context around each change.
Is my text sent anywhere to be compared?
No. The comparison runs in this page, in your browser. Open your network tab and you will see no request while you type.
How much text can it compare?
128 KiB and two thousand lines per side. Line comparison gets slower as both texts grow, and past those limits the page would stop responding instead of finishing, so it stops with a clear message.
Why does an edited line show as one row rather than a deletion and an addition?
Because that is what happened. When a removed line and an added line sit at the same position they are paired into a single changed row, and the words that actually differ are underlined inside it.
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