Text Diff Checker Online — Compare Two Texts and Find Differences
Compare two texts
Unchanged
Compare two texts side by side and instantly see which lines were added, removed, or left unchanged — additions are tinted green, deletions red, and identical lines stay neutral so the delta is obvious at a glance. An efficient LCS-based diff algorithm keeps the comparison fast and accurate even for long documents, with no artificial size cap on input. Run a content audit to verify title-tag and meta-description edits before publishing, review editor feedback against your original draft, or compare legal and compliance text versions to confirm exactly what changed between revisions. Everything runs 100% locally in your browser — sensitive contracts, NDA drafts, and unpublished content never leave your device. There are no servers, no accounts, and no upload limits — paste your text and get the diff instantly.
Line-by-line comparison for edits, contracts, and source code
Paste two versions of a contract, an SEO rewrite, or a code snippet and the diff view highlights every added line in green, every removed line in red, and unchanged context in between — making it obvious which clauses moved, which paragraphs were cut, and which lines were rewritten. The underlying algorithm is an efficient longest-common-subsequence pass that stays responsive on multi-thousand-line inputs. Use it before every content revision to make sure no keyword phrase, legal clause, or code branch was lost in the edit.
Local diff for confidential and regulated text
Everything is compared in your browser with no upload, no logging, and no API call — important for NDAs, MSA redlines, HIPAA-protected patient notes, and source code covered by an NDA. Drop in two chunks of any length and the diff appears instantly, with no file-size warnings and no third-party service in the middle. That makes it safe to use on real client work that a SaaS diff tool would block under its terms of service.