Protect PDF

Add a password to a PDF with AES-256 encryption, and choose whether readers may print, copy or edit it.

How to use Protect PDF

Choose a PDF to protect.
Type the Password to open, then Repeat password.
Optionally set an Owner password and the Permissions for printing, copying and editing.
Click Protect PDF and download the encrypted file.

Frequently asked questions

How do I put a password on a PDF?

Open the PDF, enter a password twice, and click Protect PDF. Anyone opening the downloaded file will be asked for that password.

What encryption does it use?

AES-256, the strongest encryption PDF supports, applied by qpdf running in your browser.

What is an owner password?

It controls permissions such as printing and copying. If you leave it empty, a long random one is set for you so the restrictions can't be lifted with a blank password.

Is it safe to encrypt a PDF online?

Here the file and password never leave your device: encryption happens in your browser, so nothing is uploaded.

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