Compare two Word documents — privately, in your browser
To compare two Word documents, drop both .docx files into Diffesq: it shows every difference as a synchronized side-by-side view and a consolidated redline, without uploading either file. The comparison is structural — paragraphs, headings, lists, tables, formatting, headers/footers, notes, comments, fields, and images — not a flattened text diff.
Because everything runs locally in your browser, it's suited to documents you can't send to a third-party service: contracts, agreements, board papers, anything confidential.
How it works
- Open the Diffesq workbench and drop a .docx file on each side.
- Diffesq parses both documents on your device and computes a structural comparison of the document models.
- Review the differences two ways: a synchronized side-by-side view of the rendered pages, or a consolidated redline. A change panel, structure map, and summary help you navigate.
- Export the comparison as an HTML report, PDF, JSON manifest, or CSV summary (Pro) — generated locally, never server-side.
What the comparison covers
- Paragraphs and runs, character/paragraph formatting, headings, numbered and bulleted lists, and tables including merged cells.
- Page geometry (size, orientation, margins, columns), manual page and section breaks, headers/footers, page-number fields, and inline images.
- Documents with existing tracked revisions compare in their original, pre-revision state — with a notice saying so — so old edits aren't reported as new differences.
- When a document uses features the high-fidelity renderer can't fully reproduce, that pane switches to a clearly-labeled approximate view; the comparison results stay correct either way. SmartArt, charts, equations, and embedded media are inventoried and disclosed, never silently dropped.
- Target size: up to 25 MB / roughly 500 pages per document.
Free vs Pro
Structured-file comparisons run in full on your device on the free tier, with about a third of the results shown as a preview; Pro unlocks the complete results and clean, unwatermarked exports (HTML, Markdown, JSON, PDF).
See Pricing for plans — $2.97/month, $27.99/year, or $49 once.
Privacy
Every comparison runs locally in your browser. Your files are never uploaded — there is no server that receives them, and the page keeps working with Wi-Fi turned off. Details in the Privacy Policy.
Frequently asked questions
Is this the same as Word's built-in Compare?
It serves the same job — showing what changed between two drafts — but runs entirely in your browser with nothing installed and nothing uploaded. Diffesq compares and reports; it does not edit, merge, or accept/reject changes inside the document.
Are my documents uploaded anywhere?
No. Both files are parsed and compared on your device. There is no server that receives your documents.
What about password-protected files?
Password-protected and macro-enabled (.docm) documents aren't supported in this release.
Do I need an account?
No. Comparisons run without any signup. Pro features unlock with a license key — still no account or login.