Code & Text Diff Checker

The Code & Text Diff Checker is a free, browser-based tool that compares two versions of any text or code and highlights exactly what changed. It uses a Myers diff algorithm - the same algorithm used by Git - to compute the minimal set of additions and deletions needed to transform the original text into the modified version. All processing happens locally in your browser; your code is never sent to any server.

The tool supports inline character-level diffing for modified lines, so you can see not just which lines changed but exactly which characters within those lines are different. It also supports collapsing unchanged sections to keep the view focused on what matters, and provides export options including standard .patch files compatible with the Unix patch command and Git.

Use the ignore whitespace option to skip over formatting-only changes like re-indentation, and ignore case to treat uppercase and lowercase letters as identical. The language selector labels the diff with the appropriate language name for context - useful when exporting or sharing diffs with teammates.

Side-by-side view displays the original and modified text in two columns. Deleted lines appear on the left in red, added lines appear on the right in green, and unchanged lines appear in both columns. This layout makes it easy to compare corresponding sections and understand the context of each change.

Unified view shows both versions in a single column, with removed lines prefixed by - and added lines prefixed by +. This is the same format produced by git diff and is the standard format for patch files. It uses less horizontal space and is better suited for narrow screens or long lines.