Drag & Drop PDF Files Here
Upload exactly two PDF files or click to select
What is ZyncPDF?
ZyncPDF is an open-source, privacy-first suite of powerful PDF tools built for speed, simplicity, and total user control. We believe your documents should stay yours — always. Every operation in ZyncPDF happens directly inside your browser, meaning your files never leave your device. With no uploads, no tracking, no ads, and no registration, ZyncPDF provides a smooth, secure, and 100% private experience for all your PDF tasks — from converting and merging to compressing and editing.
Why use our Compare PDFs tool?
- Visual Differences: See pages side-by-side with clear diff overlays to spot changes quickly.
- 100% Private: Runs entirely in your browser. Files never leave your device.
- Open Source & Free: No registration, ads, or limits.
- Works Offline (after load): Once assets load, you can continue comparing without a network connection.
How to use the Compare PDFs tool
- Step 1: Drag and drop exactly two PDF files into the upload area, or click to select them.
- Step 2: Click the "Process Files" button to render both PDFs.
- Step 3: Review the side-by-side pages with difference highlights.
Frequently Asked Questions (FAQ)
No. All processing happens locally in your browser. Your files never leave your device.
The tool renders both pages and computes a pixel diff overlay to visually highlight changes in layout, text rendering, and images.
No, this tool is designed for two-file comparisons only. Please upload exactly two PDFs to enable processing.