Compare PDF Text
Extract the text of two PDFs and show what changed between them.
Fill in the form and press “Compare documents” to see the result here.
How to use it
- 1Select your PDF, or drag and drop it onto the upload area.
- 2Adjust the options if you need something other than the defaults.
- 3Press the button. The document is processed on your device - nothing is uploaded.
- 4Download the result. Your original file is untouched.
About the Compare PDF Text
Both documents are read with pdf.js, the text is extracted, and the two are compared line by line with the same longest-common-subsequence algorithm version control uses.
This compares words, not layout. A document that was reformatted but not reworded will show as identical, which is usually what you want when checking a contract for changes.
Scanned documents have no text layer and will appear empty - text recognition would be needed first.
Questions people ask
Is my PDF uploaded to a server?
No. The document is read and rewritten by JavaScript in your own browser. Nothing is transmitted, which is the only sensible arrangement for contracts, invoices, medical records and anything else people put in a PDF.
Does it show visual differences too?
No. It compares extracted text. For a visual comparison, render both documents to images with the PDF to PNG tool and use the image difference viewer.
Is your document uploaded to a server?
No. This tool runs entirely in your browser using standard web APIs, so your document never leaves your device. You can confirm it by opening your browser's network panel while the tool runs, or by disconnecting from the internet after the page has loaded.
Is it free, and do I need an account?
Yes, it is free, and there is no account, no sign-up and no watermark on the result. The project is funded by optional donations.