Advanced
Compare PDF
Diff two PDFs
Side-by-side text diff between two PDFs to surface every change.
Browse all toolsFiles processed in your browser — never uploaded
In your browser
Files never leave your device.
Instant
No signup, no upload queue.
Free forever
All tools, no paywall, no watermarks.
No tracking
We don't keep or analyze your files.
How to use Compare PDF
Step 1
Load a PDF
Upload the scanned PDF, photo, or document you want to analyze.
Step 2
Configure the run
Pick the language for OCR, choose pages to compare, or mark areas to redact.
Step 3
Analyze locally
Heavy lifting runs in your browser through WebAssembly — no data leaves your device.
Step 4
Export the result
Save the OCR text, comparison, or redacted PDF with a branded filename.
Frequently asked questions
Everything we get asked most often about Compare PDF.
Are my files uploaded to a server?
No. Every conversion runs inside your browser using WebAssembly. Your files never leave your device — not even temporarily.
Is the output watermarked or limited?
No watermarks, no signup wall, no size cap beyond what your browser can handle. Every download is yours, plain and unbranded inside the file.
Does this work on mobile?
Yes. The tool works in any modern browser on iOS, Android, Windows, macOS, or Linux. Large files may run faster on a desktop, though.
Why does this tool feel slower than the rest?
Advanced tools (OCR, redaction, comparison) do significant work on every page. Larger documents take longer, but everything still runs locally.
Is redaction truly irreversible?
Yes when using Secure mode — the page is rasterized so the text under the black bar is destroyed. Fast mode only paints over text and should be avoided for sensitive data.