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Protect PDF

Add a password and permissions to a PDF.

Last updated 27 June 2026

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How to use Protect PDF

About 15 seconds, start to finish.

1
Open the protector
Visit /tools/pdf/protect-pdf.
2
Upload the PDF
Drag-and-drop or pick. The file uploads over HTTPS; we hold it in memory only.
3
Set a password
4+ characters. The same password unlocks both reading and full edit permissions.
4
Click Protect PDF
Server-side qpdf encrypts with AES-256 in under 5 seconds.
5
Download
Encrypted PDF downloads automatically. The original on your machine is untouched.

Frequently asked about Protect PDF

What encryption is used?

AES-256 — the strongest standard PDF supports. All modern readers (Adobe, Preview, Chrome) handle it without issue.

Can you recover a lost password?

No — and neither can anyone else with the document. AES-256 is not crackable at consumer scale. Store the password somewhere safe before encrypting.

Does this stop screenshots / printing?

We set both passwords identically, which means anyone who can open the file gets full permissions. For granular controls (allow view, deny print) use the qpdf CLI directly or wait for our advanced-permissions UI in V2.

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