MutandisDownload

Word’s Compare, without Word.

Mutandis turns two drafts of a contract into a tracked-changes redline at Word’s own granularity. On your own machine, in seconds, with no Word installation and nothing sent to the cloud.

Download for WindowsSee how it compares

Installs for the current user, no administrator rights

The Mutandis window, drawn for this page with a sample agreement.

A redline your reviewer can trust.

Mutandis writes real Word tracked changes, the kind you accept and reject in Word, and the round trip is tested on every scenario in its suite and on a corpus of real-world Word documents: accept every change and you get the revised draft, word for word; reject every change and you get the original.

The redline Mutandis writesExactly the revised draftExactly the original draft

7.2The Supplier shall indemnify the Customer against any directall losses arising from a breach of this Agreement, up to the cap in clause 9.1, provided that the Customer notifies the Supplier within thirty (30) dayspromptly after becoming aware of the claim and allows the Supplier to conduct its defence.

Word by word
A changed figure or name is one replaced word, never a confetti of characters. Word boundaries follow Word’s own compare output.
Insertions first
Inserted text comes before deleted text, inside a change and across whole paragraphs, the order Word writes.
Moves
A clause that leaves one place and arrives at another is tracked as a move at both ends, across the body, tables and content controls.
Tables
Rows are matched by similarity; inserted, deleted and moved rows and cells are tracked as rows and cells.
Notes, headers, footers
Footnotes, endnotes, headers and footers are compared inside, with their own tracked changes.
Formatting
Bold, italics, styles, numbering and indents become tracked formatting changes, or are left out when you ask.

Two right-clicks.
No dialogs.

  1. Right-click the original in File Explorer and choose Compare with Mutandis.
  2. Right-click the revised draft the same way. The window collects both and compares on its own.
  3. Read the counts, walk the changes with Alt + ↓, and save the redline with Ctrl + S. It opens in Word, ready to accept or reject.

Drafts can also be dropped on the window, typed, or picked from the folder pane, which keeps every version of a document one click away. The window follows Windows’ light or dark setting and compares PowerPoint decks slide by slide, too.

Review the changes, then send the reasons.

The comparison stays open as a reading view in the page layout of the document itself. Work through it like a review, not a printout.

  • Tag, note and tick off each change. Tag every technical-looking change in one go and focus on the rest.
  • Group changes made for one reason and write the rationale once. It goes to the client with them.
  • Word comments from both drafts sit under the paragraph they belong to, replies and resolved threads included.
  • Export a PDF report with a cover of counts, the changes and their rationale, the redline on the document’s own pages and a numbered list of changes.

Built for the whole negotiation, not one comparison.

A project is a matter folder with every version of every document, who sent it and when. Mutandis compares each new draft with the last one you sent.

  • Catch untracked changes. Edits the other side made without tracking them, a silently rejected change of yours included, are marked inside the comparison.
  • Keep an issues list that carries over from round to round, and export it to Word or Excel as an issues list or a response-to-comments schedule.
  • Send the client a key-changes memo each round: the decisions they need to make and the changes that matter, by theme, as PDF or Word.
  • One report for every reader, comparing the newest draft with several earlier ones, for colleagues who last read different versions.

The same engine on the command line, and in Claude.

For legal-tech and knowledge teams: one binary with no runtime, a JSON summary for your pipelines, and a Model Context Protocol server so an assistant compares, reads and sanitizes documents by calling a tool.

Terminal
# A redline and a PDF report, with a summary as JSON
$ mutandis compare v3.docx v4.docx -o redline.docx \
    --pdf report.pdf --json

# Strip authors, dates and metadata before a draft goes out
$ mutandis sanitize v4.docx \
    --accept-changes

# Run as an MCP server for Claude and other assistants
$ mutandis mcp

Tools the MCP server offers

  • compare_documents
  • read_document
  • sanitize_document
  • list_project
  • create_project
  • add_project_version
  • compare_versions
  • check_untracked_changes
  • list_issues
  • add_issue
  • export_issues
  • export_key_changes

The command line and the server work on the same project files, reviews and issues as the desktop app.

Your drafts stay on your machine.

  • No Word installation. Mutandis reads and writes .docx itself. Open the finished redline in Word when you are ready.
  • No cloud. Documents are compared locally. Nothing is uploaded, and nothing needs an account.
  • Plain Word files. The redline is an ordinary .docx with tracked changes. Anyone with Word can open it, accept and reject.

Download Mutandis

For Windows. The desktop app and the command-line tool, together.

Download for Windows
Installer
Mutandis-win-Setup.exe
Includes
The desktop app, the command-line tool and the MCP server
Installs
For the current user, with no administrator rights; adds Compare with Mutandis to the right-click menu
Updates
Itself, the next time it starts after a new release

Setup is not code-signed yet, so Windows SmartScreen may warn the first time: choose More info, then Run anyway. Uninstall from Settings → Apps.