Compare two versions of text and see additions, removals and unchanged passages in a clean unified diff. Choose line-by-line for documents and code, or word-by-word for short edits. Everything is compared locally in your browser.
The checker uses a longest-common-subsequence comparison, not a visual screenshot. To keep the page responsive, each side is capped at 700 comparison tokens. Word mode treats whitespace as a separator; line mode preserves blank lines.