Diff Checker Online Free
Compare two texts and see exactly what changed. Additions in green, deletions in red. Browser-only, no signup.
🔒 Your file never leaves your browser. All comparison is done locally.
How to Compare Two Texts Online
- 1
Paste the original text
Paste the original version of your text into the left textarea labelled 'Original'.
- 2
Paste the modified text
Paste the new or modified version into the right textarea labelled 'Modified'.
- 3
View the highlighted differences
Click Compare. Inserted text is highlighted in green and deleted text in red. A summary shows total characters added and removed.
A diff checker is an essential tool for developers, writers, and editors who need to track changes between two versions of a document. Common use cases include comparing code before and after a refactor, reviewing contract or document revisions, verifying that a translation matches the original, or confirming configuration file changes.
This tool uses the diff-match-patch algorithm with semantic cleanup, which produces human-readable diffs aligned to word boundaries rather than raw character positions. This gives more natural-looking results for prose and code.