Text Diff Checker
Compare two blocks of text line by line and see exactly what was added, removed, or unchanged.
About the Text Diff Checker
Paste two versions of anything (a config file, a paragraph, a SQL query, an API response) and see exactly what changed, line by line. Added lines are highlighted green, removed lines red with a strikethrough, and the summary counts the changes.
It is the same kind of comparison git uses, computed in your browser using a longest common subsequence algorithm. That means the diff is minimal: lines that exist in both versions are matched up even when other lines were inserted between them, instead of everything after the first change showing as different.
Useful when reviewing config changes outside version control, comparing two API responses, checking what a colleague edited in a shared document, or verifying that a migration produced the expected output. Since nothing is uploaded, comparing confidential text is safe.
Reach developers and designers who use these tools every day. Privacy-first, no trackers.
Frequently asked questions
Does it diff by character or by line?
By line, like git. A line counts as changed if it differs by even one character; it will show as one removed line and one added line. Line based diffs are the most readable for code and config.
Why does everything show as changed?
Usually invisible differences: Windows vs Unix line endings, tabs vs spaces, or trailing whitespace. Normalize the text first if you only care about content differences.
Is there a size limit?
The diff is computed in your browser, so very large inputs (tens of thousands of lines) may take a moment. For typical files and documents it is instant.