ToolHub

PDF Protect

Add a password to encrypt your PDF

Privacy guarantee. Encryption happens entirely in your browser. Your PDF and password are never sent over the network. Open developer tools and watch the Network tab to verify: zero outbound requests carry your file.

Drop a PDF to add a password

Supports: APPLICATION/PDF

Quick steps

1

Drop your PDF

Upload any PDF you want to protect with a password.

2

Set a password and permissions

Pick a strong password. Choose what readers can do once they open the file (print, copy, edit, etc.).

3

Download

The encrypted PDF downloads instantly. Anyone opening it will be asked for the password.

Frequently asked questions

Is my password sent anywhere?

No. Both your PDF and the password stay in your browser during encryption. Open developer tools and watch the Network tab to verify: zero outbound requests carry your data.

Can the encryption be cracked?

The encryption uses standard PDF security with AES. A strong password (16+ characters with mixed types) takes longer than a human lifetime to brute force. A weak password (under 8 chars, dictionary words) can be cracked quickly.

What is the difference between the permissions?

Printing controls whether the document can be sent to a printer. Copying controls extracting text. Modifying allows editing content. Annotating allows adding comments. Filling forms allows interacting with form fields without modifying the underlying document.

What if I forget the password?

There is no recovery. The whole point of encryption is that there is no backdoor. Store the password in a password manager before you protect important PDFs.

Can I protect a PDF that is already encrypted?

No. You need to remove the existing password first using a PDF Unlock tool, then re-encrypt with the new password.