PDF Side-by-Side Diff

Compare two PDFs side by side and highlight differences in red.

PDF Diff Viewer is a fast Chrome extension that lets you compare two PDF documents side by side and instantly see what changed. Instead of switching between tabs or manually scanning pages, you get a clear visual comparison directly in your browser, with differences highlighted so you can focus only on what matters. Everything runs locally, which means no uploads, no waiting, and no risk to your data. Your files never leave your machine, making it ideal for sensitive documents like contracts, reports, or internal files. It’s lightweight, responsive, and built to give you results immediately. Whether you're a developer validating outputs, a designer checking layout changes, or just someone tired of playing “spot the difference” with PDFs, this tool saves time and reduces errors. Open it, drop your files, and you’re done.