The Text Diff Checker compares two blocks of text and highlights every addition, deletion, and change between them at line, word, or character level. Ideal for comparing document versions, configuration files, code snippets, or any plain text. Powered by the Myers diff algorithm — the same algorithm used by Git. Supports synchronized scroll in split view and lets you export the unified diff as a .patch file.
Frequently Asked Questions
What algorithm does the diff use?
The Myers diff algorithm — the same method used by Git. It finds the minimal set of edits needed to transform one text into another.
What do the colors mean?
Green highlights are additions present in the right text but not the left. Red highlights are deletions present in the left text but not the right.
Can I compare source code files?
Yes. Paste any code into either panel — the tool treats it as plain text and highlights all differences regardless of programming language.
Is there a size limit?
The tool runs in your browser so very large inputs over 1 MB may slow performance. For typical document or code comparison it handles any reasonable size instantly.
Can I export the diff as a .patch file?
Yes. Click "Download .patch" to save a standard unified-diff patch (the same format produced by git diff and consumed by patch/git apply). The split view also supports synchronized vertical scroll so both panes stay aligned as you review.