Compare two versions of a Word document without Word, without an account and without sending the files to a server. Diffspot reads the paragraphs, tables, headers and footnotes of each .docx file in your browser and shows the differences word by word. OpenDocument (.odt) files work too.
How to compare Word documents
- Drop the original .docx on the left.
- Drop the revised .docx on the right.
- Review the redline or switch to side by side to read both versions in parallel.
- Export a report or print it to PDF.
Why Diffspot
- PrivateDocuments are unzipped and read locally by a Rust engine compiled to WebAssembly.
- Redline viewInsertions and deletions are marked word by word, like Track Changes.
- Tables and notes includedTable cells, headers, footers, footnotes and comments are part of the comparison.
- Fast on big inputsThe diff engine is written in Rust and runs in a background thread, so typing stays smooth. Files with hundreds of thousands of lines compare in about a second.
- Free, no accountEvery feature is free with no sign-up and no size paywall. Ads pay for the site, and they run in an isolated frame that can't read the page.
- Works offlineAfter your first visit the app is cached, so it keeps working on a plane or behind a strict firewall.
Frequently asked questions
Does it compare formatting such as bold or fonts?
No, it compares the text content. Formatting-only changes don't appear.
Can I compare a Word document with a PDF?
Yes. Drop a .docx on one side and a PDF on the other; both are turned into text first.
What about old .doc files?
The legacy binary .doc format isn't supported. Save it as .docx first.
Is it safe to paste confidential text or files?
Yes. Diffspot computes every comparison on your device: the page loads the engine once, then your text and files stay in the browser tab. There is no upload and no server-side storage, and ads are shown in a separate sandboxed frame that cannot read the page. How Diffspot works explains the details, and you can confirm it in your browser's network panel.