Compare PDF

Compare two PDFs without uploading them.

See exactly what changed between two versions of a document: additions, deletions, moved text. Both PDFs stay on your device throughout.

A document sealed inside a Faraday cage. Your files stay fully private, on your device. A document sealed inside a Faraday cage. Your files stay fully private, on your device.

Two versions of a contract are twice the sensitive content.

Document comparison is a review task, which means both versions are almost certainly sensitive. Uploading a contract, a brief, or a policy to a third-party compare service means sending both the old version and the new one to a server you don't control.

The difference in one sentence

Comparing two versions of a confidential document shouldn't require uploading both of them to someone else's server.

KeptPDF extracts and diffs the text content of both PDFs entirely in your browser. No upload endpoint, no server processing. Both files stay local. You can check the Network tab while comparing: neither file ever appears in a request.

How to compare two PDFs

On your device. No account needed, and nothing gets uploaded.

1. Open both PDFs

Drop in the original and the revised version. Both load in your browser. Neither is uploaded.

2. View changes

KeptPDF highlights additions in green and deletions in red, with a side-by-side view showing the differences across every page.

3. Review and save

Step through every change, or download the redline comparison as a PDF.

Exact changes. Both files stay local.

Word-level diff

Changes are highlighted at the word level, not just the paragraph. Additions appear in green, deletions in red, making it easy to spot even a single modified word in a long contract.

Side-by-side view

The original and revised versions appear side by side with synchronized scrolling so you can see context alongside the highlighted changes.

No upload

Both documents are compared in your browser. Neither file is transmitted to any server at any point.

Free, no account

Compare PDFs free with no sign-up, no daily limit. Pro ($29/month) supports larger files (hundreds of MB practical limit, browser memory dependent).

After reviewing the changes

Two sides of the same job, both running entirely on your device.

Questions, answered.

How do I compare two PDFs and see the differences?
Open KeptPDF's Compare tool, drop in the original PDF and the revised version, and KeptPDF highlights every addition and deletion across all pages. Step through changes or view them all at once. Free with no account, no daily limit.
Does it compare exact text or just visual differences?
Text content. KeptPDF extracts the text from both PDFs and runs a word-level diff, the same kind used in code review tools. This finds all wording changes, additions, and deletions, including single changed words in a dense paragraph.
Will it work on scanned PDFs?
Scanned PDFs need text to compare. If your PDFs are scanned images, run OCR on them first using the OCR tool, then compare the resulting searchable versions.
Are both documents uploaded to a server?
No. Both PDFs are processed in your browser. Neither is transmitted anywhere.
Can I download the comparison result?
Yes. You can download the redline comparison as a PDF showing the highlighted changes.
Is it free?
Yes: free with no account, no daily limit. Pro ($29/month) supports larger files (hundreds of MB practical limit, browser memory dependent).

Compare PDFs. Free, in your browser.

Open Compare PDF