Text Diff Checker
Find additions, removals and unchanged content with a local line-by-line or word-by-word longest-common-subsequence diff.
Compare two versions of text
Find additions, removals and unchanged content with a local line-by-line or word-by-word longest-common-subsequence diff.
How the text diff checker works
A text diff highlights what changed between an original and a revised version. This browser tool uses a longest-common-subsequence comparison to align matching content and then marks insertions and deletions around that shared sequence.
Line diff versus word diff
Line mode is useful for articles, configuration snippets, notes and documents where each line is meaningful. Word mode is better for examining copy edits inside prose. Choose the coarser line mode for larger drafts because word-level dynamic programming uses more browser memory.
Reading the output
Lines or tokens prefixed with a plus sign exist only in the revised version. A minus sign identifies content only in the original. Unchanged units are prefixed with two spaces. This is a textual comparison and does not interpret whether a change is factually correct.
Privacy and performance
The comparison runs locally. To avoid freezing a browser tab, the interface imposes a per-side unit limit for the dynamic-programming matrix.