Free Online Text Compare — Diff Tool for Documents, Code & Files

Compare any two versions of text, code, or documents side by side and see exactly what changed — highlighted in real time as you type. No button needed, no sign-up, no software. A free online diff tool trusted by developers, writers, editors, QA testers, and legal professionals who need to know precisely what changed between two versions of a document.

How the online text diff works

Paste your original text in the left pane (Text A) and your updated text in the right pane (Text B). Differences appear instantly, highlighted by colour:

🟢 Green lines — content added in Text B that was not in Text A
🔴 Red lines — content removed from Text A that is not in Text B
🟢🔴 Darker word highlights within a changed line — the exact words that changed (Word Level) or the exact characters (Letter Level)

9 Online Compare Modes

Online Text Compare — compare any plain text, articles, essays, or documents
Online SQL Compare — compare SQL queries, stored procedures, and schema changes
Online JSON Compare — auto pretty-prints both sides before comparing, so formatting differences do not mask real changes
Online XML Compare — auto pretty-prints XML for clean structural comparison
Online HTML Compare — compare HTML source code between versions
Online CSS Compare — compare stylesheets and detect changed rules
Online JavaScript Compare — compare JS files and find changed functions
Online Excel Compare — upload .xlsx or .xls files, text is extracted and compared automatically
Online PDF Compare — upload PDF files, text is extracted and compared (text-based PDFs only)

Upload files directly

Click 📂 Upload in either pane header to load a file from your computer. Supported formats: .txt, .md, .sql, .html, .css, .js, .json, .xml (up to 5 MB), .xlsx/.xls Excel files (up to 5 MB), and .pdf PDF files (up to 10 MB).

Word Level vs. Letter Level

Word Level (recommended) highlights entire changed words — cleaner and easier to scan. Letter Level highlights individual changed characters within words — use this for maximum precision when comparing code, serial numbers, or data with single-character differences.

Who uses an online diff tool?

Developers — compare code versions, config files, and SQL migrations
Writers & editors — track changes between manuscript drafts
Legal teams — compare contract versions to find changed clauses
QA testers — compare expected vs. actual API responses
SEO professionals — compare page content before and after updates