Text Diff Checker

How to use

1. Open this page on any device — no signup needed.
2. Fill in the fields above.
3. Get your result instantly — nothing is uploaded.

About this tool

A diff checker compares two texts and highlights the differences — indispensable for reviewing contract edits, article revisions, config files and code changes. This tool does a line-level comparison (LCS algorithm) with removed lines in red, added lines in green. For very large files, compare section by section.

Compare Two Texts Side by Side

Paste the original in the left box and the new version in the right, and this text diff checker highlights exactly what changed: insertions, deletions, and edits marked at word level so a one-word swap does not repaint the whole paragraph. Everything runs inside your browser — neither text ever leaves your device, which is why writers use it for unpublished drafts and developers use it for config snippets that would be careless to paste into a random website. For character-exact work (code, legal clauses), read the diff line by line; for prose, compare paragraph by paragraph and let the highlights show the moved phrases.

Who Uses a Diff Checker Day to Day?

Writers and editors compare draft revisions to show a client precisely what changed between versions. Developers paste two versions of a config, a JSON payload, or a snippet to spot the one line that broke a build. Students and researchers check paraphrasing against the original source. SEO and content teams compare old and new title tags or meta descriptions before publishing. Translators verify that an edit to the source text is reflected in the translation. The common thread: you need to know what changed, not just that something did.

After the diff is clean, the word counter gives you length limits at a glance, and the free case converter fixes uppercase headings or lowercase URLs without retyping. All three tools share the same privacy rule: local processing, no uploads, no sign-up.

FAQ

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