Compare PDFs
Load two versions of a document, flip through pages side by side, and toggle a difference overlay that highlights changed areas in red.
Original PDF
Revised PDF
Page /
% of pixels differ on this page
Frequently asked questions
Are my PDF files uploaded to a server?
No — this tool runs entirely in your browser using WebAssembly and JavaScript. Your files never leave your device, which also means there are no size limits and no queues.
How does the difference highlighting work?
Both pages are rendered at the same scale and compared pixel by pixel; areas that differ are marked red and a change percentage is shown. It catches layout, image and text changes alike.