Switching back and forth between two open PDFs is tedious, and most desktop software that puts documents side by side is either expensive or overkill for a simple comparison task. This tool takes a more direct approach: it combines both PDFs into a single file, with each page showing both documents next to each other, so you can scroll through and compare without juggling windows.
It works entirely in your browser. No files are uploaded, nothing is stored on a server, and your documents stay on your device throughout the process. It's free, it's instant, and it works for contracts, translations, research papers, or anything else you need to read side by side.
When to Compare PDFs Side by Side
Side-by-side PDF comparison is ideal for these specific scenarios:
Document Version Comparison
Compare different versions of contracts, legal documents, or manuscripts to identify changes, additions, or deletions between revisions.
Translation Verification
Place original and translated documents side by side to verify translation accuracy, check for omissions, and ensure quality assurance.
Before and After Analysis
Display original and edited versions of reports, proposals, or design documents side by side for easy reference and change tracking.
Legal Document Review
Compare legal documents, contracts, or agreements to identify modifications, review terms, and ensure accuracy across different versions.
How to Compare PDFs Side by Side
Select Your PDFs
Choose two PDF files you want to compare. Drag and drop or click to browse—both methods work seamlessly.
Choose Merge Options
Select how to handle page sizes: scale to fit, stretch to fill, or use larger size. The tool automatically pairs corresponding pages.
Download and Compare
Click merge and download your combined PDF. Each page shows both documents side by side, making comparison effortless.
Privacy for Document Comparison
When you're comparing contracts, legal filings, or anything else confidential, the last thing you want is those files passing through a third-party server. This tool processes everything locally in your browser, so your files stay on your device the whole time.
There's no upload, no account, and no way for anyone else to access what you're working with. Learn more about how the privacy side works.
Frequently Asked Questions
Is this PDF comparison tool completely free?
Yes, it's 100% free with no limits, no watermarks, and no hidden fees. You can compare as many PDFs as you want without any restrictions.
Are my PDF files uploaded to any server?
No. All processing happens directly in your browser using JavaScript. Your files never leave your device, ensuring complete privacy for sensitive documents.
Can I compare PDFs with different page sizes?
Yes. The tool offers multiple options: scale pages to fit, stretch to fill, or use the larger page size. It automatically handles PDFs with different dimensions.
Does this tool work offline?
Once the page is loaded, the PDF processing works entirely in your browser. However, you need an internet connection to initially load the page.
What browsers are supported?
The tool works on all modern browsers including Chrome 90+, Firefox 88+, Safari 14+, and Edge 90+. It also works on mobile browsers.