Crowdsourced Redlines

What Crowdsourced Redlines is

Crowdsourced Redlines compares two Microsoft Word .docx files and creates a third file marked with native Word tracked changes, including insertions, deletions, and moved text. Reviewers can accept or reject each change individually in Word. Its comparison engine also detects formatting changes and improves table handling. In the browser, the comparison runs locally through WebAssembly in a Web Worker, and the resulting document downloads directly to the device; the default browser workflow does not upload files to a server. An optional server-side API processes documents in memory and stores nothing. The engine is described as a .NET 8 WebAssembly update of Microsoft’s archived Open-Xml-PowerTools comparison engine. The engine, viewer, Python wrapper, and web app are MIT-licensed and publicly developed on GitHub. Users can self-host, audit, or embed the code, with developer packages for TypeScript or JavaScript, Python, and C#/.NET. Users can file a public ticket with source files when a comparison is poor; the ticket becomes a regression-test fixture. The tool is free, with web, API, and self-hosting options.

Who it suits

It suits people who need to compare Word documents and review changes in Word, as well as developers who want to integrate or self-host an open-source comparison engine.

Limits

The described web tool compares Microsoft Word .docx files. The listed Free plan costs nothing.

Getting started

1. Open https://redlines.opensource.legal/.
2. Use the web app to compare two Microsoft Word .docx files.
3. Download the resulting document to your device.
4. Review and accept or reject individual tracked changes in Word.
5. For development or deployment, use a listed language package or self host the codebase.

Verdict

Crowdsourced Redlines focuses on .docx comparisons, with local browser processing and native tracked-change output. Its public-ticket process and Word document scope are important considerations.