Compare PDF is a free online PaperStack tool for pdf tools. Put two PDFs side by side and spot what changed.
Compare PDF helps you review two versions of a document — a contract v1 vs v2, a revised quote, a policy update. Seeing both at once is faster than flipping windows.
You can use it on a phone, tablet, or computer. There is no sign-up, and processing runs in your browser so files and text are not uploaded to PaperStack for storage.
How Compare PDF is useful
People miss a single clause change in a 20-page file. A visual compare, done locally, is safer than uploading legal PDFs to an AI site.
Typical reasons people open this tool:
- Finish a one-off job without installing desktop software
- Keep documents and copy on the device they already use
- Move faster than emailing a file to themselves or waiting on IT
- Pair it with other PDF Tools on PaperStack in the same sitting
Who this tool is for
Students
- Check a teacher’s annotated PDF against your original
- See what changed in a group-project draft
- Compare two versions of a lab report
Office and business
- Review redlines on a vendor contract
- Confirm an invoice revision
- Audit a policy PDF against last year’s file
Creators, freelancers, and developers
- Compare two PDF proofs
- Spot copy changes in a client round
- Check that a reprint matches the approved PDF
How to use Compare PDF
- Upload both PDFs.
- Scroll them side by side.
- Note differences, then save or continue in another tool.
The tool page is https://paperstack.in/pdf-tools/compare-pdf/.
Practical tips
- Use similarly exported PDFs — a scan vs a digital file is harder to compare.
- For text-only diffs, extract text and use Text Compare.
- Protect the newer file after you approve it.
Why use PaperStack for this
Many “free converters” ask you to upload a file to a server you do not control. PaperStack is built around browser-side processing: you open the page, do the work, and download or copy the result. That is the difference when the file is a payslip, a contract, a customer CSV, or a draft that is not public yet.
You also get a consistent layout across PDF, Word, image, CSV, and text tools, so the next job does not require learning a new app.
Frequently asked questions
Is Compare PDF free?
Yes. You can use it without creating an account or paying a subscription.
Are my files uploaded?
No. Processing runs locally in your browser. PaperStack does not need your file on a server to run the tool.
Does it work on mobile?
Yes. Use a modern mobile or desktop browser. Very large files are more comfortable on a laptop because they use more memory.
Can beginners use it?
Yes. Follow the steps above. If something looks wrong, keep the original file and try a milder setting (for example less compression).
Related PDF Tools
- Merge PDF
- Split PDF
- Compress PDF
- JPG to PDF
- WORD to PDF
- Unlock PDF
See every tool in this category at https://paperstack.in/pdf-tools/
Conclusion
Compare PDF is useful whenever you need this job done quickly, privately, and without extra software. Open it when the file is in front of you, finish the steps, and keep the original as backup.
Start here: https://paperstack.in/pdf-tools/compare-pdf/