Free Document Compare
Document Compare finds the differences between two PDF, Word (.docx) or plain-text files word by word, in any combination. Added words appear in green and removed ones struck through in red, inline or side by side, with a similarity score. You can ignore case or spacing and download the redline as a text file.
- Input:
- PDF, Word .docx, plain text
- Views:
- Inline redline or side by side
- Limit:
- About 120,000 words in total
- Price:
- Free
- Runs:
- Locally, in your browser
- Uploads:
- None: files never leave your device
- Account:
- Not needed
Quick answers
Are my documents uploaded?
No. The text is extracted and compared entirely in your browser; the files never leave your device.
Can I compare a PDF with a Word file?
Yes. Any mix of PDF, Word .docx and plain text works, because both are reduced to their text before comparing.
Processed on your device: your files are never uploaded. How it works
Network activity in this tab
What this page has requested since you opened the site in this tab. An upload is any request that sends data: POST, PUT, PATCH or a request with a body.
No uploads: nothing has been sent from this page.
No network requests yet.
To see every request, open your browser's developer tools (Network tab).
How to use the Document Compare
- Drop the original as document A and the changed version as document B (PDF, Word .docx or text). Nothing is uploaded.
- Read the inline redline, or switch to side by side; green is added, red struck-through is removed.
- Use ignore-case or ignore-spacing if you only care about wording, and download the redline as a text file.
Credits & open source
Our own code plus open-source libraries. Thank you to the people who make these projects.
- PDF.jsRenders PDF pages to images and thumbnails. © Mozilla Foundation and contributors · Apache-2.0
- MammothConverts Word .docx documents to clean HTML. © Michael Williamson · BSD-2-Clause
Web platform APIs used: File API.
Full license texts: third-party notices · all credits
Frequently asked questions
Does it compare formatting and layout?
No, it compares the words. Fonts, colors, tables and page layout are not part of the comparison. A scanned PDF with no text layer must be run through OCR first.
What does the similarity score mean?
The share of words the two documents have in common, from 0% (completely different) to 100% (identical text).