Compare Two PDFs and Highlight the Differences
Spot what changed between two versions of a contract, policy or report. Drop in both PDFs and PDFSpark compares their text page by page, highlighting added and removed words side by side, and can overlay the two versions of a page to show visual changes too. Neither document leaves your device.
Your file is processed by your own browser and never uploaded. Most online tools send your document to their servers and delete it later — this one never receives it at all.
Why use Compare PDFs
- Page-by-page text comparison that copes with inserted or removed pages
- Removed and added words highlighted side by side
- Jump between changed pages
- Visual overlay that highlights changed pixels
- Download a plain-text report of the changes
- Both files processed locally, never uploaded
Popular uses
- Check what a counterparty changed in a revised contract
- Review edits between drafts of a policy or manual
- Verify that a final PDF matches the approved version
Compare PDFs: frequently asked questions
How do I compare two PDF files for differences?
Open both versions in PDFSpark's Compare PDF tool, the original first and the revision second, and click Compare. The text of each page is extracted and matched in your browser, and removed and added words are highlighted side by side so you can review every change. Neither file is uploaded.
Can it compare scanned PDFs?
Visually, yes; word by word, only after OCR. Scanned documents are images without a text layer, so the text comparison has nothing to read, but 'Show visual differences' overlays the two versions of a page and highlights the pixels that changed. For a word-by-word comparison, run each scan through OCR PDF first, keeping in mind that OCR errors can show up as false differences.
Does it detect formatting or image changes?
The text comparison focuses on words: text added, removed or changed. Fonts, colours, layout and images aren't part of it. For those, use 'Show visual differences' on a page, which renders both versions and highlights every pixel that changed, in red for the original and green for the revision.
Is it safe to compare confidential contracts?
Yes. Both PDFs are opened and compared inside your browser, so neither version is sent to a server. That matters for draft agreements, pricing and negotiation documents, which are exactly the files people compare most often. Nothing is kept once you close the tab.
How is this different from Word's compare feature?
Word compares editable documents and needs the original Word files. PDF comparison works when you only have the PDFs, for example when a counterparty sends back a revised PDF. It compares the extracted text, so it can't reproduce Word's formatting-level change tracking.