Password Protect a PDF

About Protect PDF

Adds real AES encryption to the file itself, not a token restriction a reader can ignore. Without the password the contents cannot be read, and you can separately restrict printing, copying, and editing.

How to protect PDF

1. 1

   Drop your PDF files onto the box above, or click to browse for them.

2. 2

   Adjust the settings if the defaults are not what you need.

3. 3

   Press Protect PDF. The work happens on your device, so the time it takes depends on your machine rather than a queue.

4. 4

   Download the result. Nothing is stored, so grab it before you close the tab.

Questions about protect PDF

What happens if I lose the password?

The document is unrecoverable. Encryption with no back door is the entire point — we cannot reset it, and neither can anyone else. Store the password somewhere safe before you send the file.

How strong is the encryption?

256-bit AES, the strongest option in the PDF specification and the same standard used by Acrobat. A strong, unique password matters far more than the cipher — most real-world failures are guessable passwords, not broken maths.

Is Protect PDF really free?

Yes — every tool on PDF Love is free, with no account, no email, no trial period, and no watermark stamped on your output. There is no file-count limit and no daily quota.

What happens to my files?

They never leave your device. This tool runs entirely inside your browser using WebAssembly, so your file is read from local memory, processed locally, and handed straight back. Nothing is uploaded, which is why it still works with your Wi-Fi switched off.

Is there a file size limit?

There is no limit imposed by us. Because the work happens on your own device, the practical ceiling is your available memory — comfortably a few hundred megabytes on a normal laptop or phone.

Does it work on a phone or tablet?

Yes. The site is built mobile-first and works in any modern browser on iOS, Android, Windows, macOS, and Linux. There is nothing to install.