Protect PDF – free online
Protect PDF files with a password. Encrypt PDF documents to prevent unauthorized access.
How to use Protect PDF
- Open Protect PDF on ToolPlanet AI.
- Choose a PDF from your device, or drag and drop onto the page.
- Set a password and choose permissions.
- Download a PDF encrypted with AES-256.
Frequently asked questions
Is Protect PDF free?
Yes. Protect PDF on ToolPlanet AI is completely free, with no sign-up, no watermark and no limit on downloads.
Are my files uploaded when I use Protect PDF?
No. Protect PDF runs entirely inside your web browser, so your file never leaves your device and is not uploaded to any server.
What do I need to use Protect PDF?
Just a web browser such as Chrome, Edge, Safari or Firefox, on a computer or phone. You start with a PDF and get a PDF encrypted with AES-256.
Do I need to install software or create an account?
No. Everything works online in your browser. There is nothing to install and no account to create.
More PDF Security tools
Edit PDF in the same font
Click any text to change it. Prices, names, dates — edits keep the PDF's own font. Add text, boxes and images, then save.
or drop a PDF here · files stay in your browser