Visually Compare Two PDFs, Free — No Upload
See exactly what changed between two versions.
Document A
Select the original
Click to choose, or drop a file here
You can also paste (Ctrl+V / Cmd+V)
Most tools run entirely on your device
Document B
Select the revised version
Click to choose, or drop a file here
You can also paste (Ctrl+V / Cmd+V)
Most tools run entirely on your device
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About visually comparing two PDFs
Most free "compare PDF" tools diff text only — useful for a contract's wording, useless for a page whose layout shifted, a logo that moved, or a chart that changed. This tool renders matching pages from both PDFs to the same scale and compares them pixel by pixel, so it catches exactly the kind of visual change a text diff misses.
Every changed pixel above a small threshold (loose enough to ignore anti-aliasing noise, tight enough to catch real edits) is highlighted in red on a dimmed copy of the page, with a diff percentage per page. A page that only exists in one document is flagged rather than compared against nothing. Everything — rendering both PDFs and computing the diff — happens entirely in your browser; neither file is uploaded.
Supported files
Accepts two PDFs. Shows a highlighted diff image and a side-by-side view, page by page — no file is downloaded from this step.
Is my file uploaded?
No. Both PDFs are rendered to canvas and compared entirely in your browser.
How to Compare PDFs
- 1
Open the tool
Open the Compare PDFs tool and drop your file onto the page, or click to browse for it. Everything runs in your browser — the file is never uploaded.
- 2
Add both versions
Drop the original PDF and the changed PDF into their two slots.
- 3
Review the differences
The tool highlights what changed between the two versions, page by page.
Further reading
Compare PDFs — frequently asked questions
How is the difference percentage calculated?+
Each matching page pair is rendered as an image, and we count the percentage of pixels whose color differs beyond a small threshold — small enough to ignore anti-aliasing noise but sensitive to real content changes.
What if the two PDFs have a different number of pages?+
Pages that only exist in one document are flagged as 'Only in Document A' or 'Only in Document B' rather than compared against nothing.
Is there a free tool to compare two PDFs and see what changed?+
Yes — upload both versions and it highlights the differences page by page, free and without either file leaving your browser.
Does it compare the actual text, or just how the page looks?+
It compares how each page renders visually, pixel by pixel — so a font, color, or position change is caught even if the underlying text content is identical.
Do you upload my files to a server?+
No — every tool here processes your files entirely on your device, and nothing is uploaded to a server. The only exception is the AI tools, which send the extracted text (not the file) to Claude to do their work.
Is there a file size limit?+
There's no artificial limit we impose, but since processing happens in your browser, very large files (500+ MB or 1,000+ pages) are limited by your device's memory rather than by us.
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