Text Diff Checker

Lines mode compares the two texts line by line, which is best for comparing documents, config files, or code where entire lines are added or removed; Words mode breaks the text into words and highlights exactly which words changed within a sentence; Characters mode goes even finer, highlighting individual character changes, useful for spotting a single typo or a small edit in a short string.

Unified view shows one column with removed lines directly above the added lines that replaced them, similar to a command-line diff; Side-by-side view splits the original and changed text into two columns so you can compare them at the same vertical position, which is often easier to follow for longer documents.

It treats two lines as identical if they only differ in spaces or tabs at the very start or end of the line, which is useful when comparing code that has been re-indented. It does not collapse extra spaces in the middle of a line; if you need that, switch to Words mode, which already treats runs of whitespace between words as equivalent.

Yes, the "Download .diff" button saves the comparison in the standard unified diff format used by tools like Git and the Unix diff command, with the usual --- / +++ file headers and @@ hunk markers, so it can be applied with patch or reviewed in any diff-aware editor.

In Lines mode, the tool first determines which lines were added or removed, then, for a line that was replaced, it runs a second word-level comparison between the old and new version of that specific line so only the changed words are highlighted rather than the entire line; if a line was removed entirely with no replacement nearby, there is nothing to compare it against, so the full line is shown as removed.