Paste two versions of text and instantly see the differences highlighted line by line. Shows additions in green, deletions in red. Works for code, documents, and any plain text.
A diff checker compares two versions of text and highlights the differences — additions, deletions, and unchanged lines. It is essential for reviewing code changes, comparing document versions, and spotting edits.
The tool uses the Longest Common Subsequence (LCS) algorithm to find the maximum number of matching lines between two texts. Lines not in the LCS are marked as added or removed.
Yes. The diff checker works for any plain text including code, HTML, JSON, configuration files, and prose. Copy and paste the two versions into the text areas.
Green lines with + prefix are in Version B but not in Version A (added). Red lines with - prefix are in Version A but not in Version B (removed). Grey lines are unchanged.
This browser-based tool handles texts up to approximately 10,000 lines before performance slows. For very large files, use a dedicated tool like Git diff or VSCode compare.
This tool compares text you paste in. To compare files, open each file in a text editor, select all, copy, and paste into the respective boxes. The tool then shows differences between the file contents.
Line diff (this tool) compares entire lines and marks the whole line as added or removed. Character diff goes deeper and highlights individual changed characters within a line. Line diff is easier to read for most use cases.