Protect PDF

What is a Protect PDF tool?

A Protect PDF tool adds a password to a PDF file so that only people who know the password can open it. This tool encrypts the document with 256-bit AES (AES-256) and can also apply permission restrictions for printing, copying text and editing. It is a good choice before sharing invoices, ID documents, contracts or any other PDF that should not be readable by everyone.

How to protect a PDF with a password

1. Click the file input and choose the PDF you want to protect — its first page preview appears.
2. Enter a password and confirm it. The password must be at least 4 characters.
3. Optionally open Advanced permissions and switch off printing, copying or editing.
4. Press the Protect PDF button and wait while the file is encrypted on the server.
5. Click Download Protected PDF to save the encrypted file, and keep the password somewhere safe.

Why use this tool

• Free to use with no signup or account needed.
• Encrypts the file with strong 256-bit AES (AES-256) protection.
• Optional restrictions for printing, copying text and editing.
• Works on phone, tablet and desktop through your browser.

Frequently Asked Questions

Is it free to protect a PDF here?

Yes. Protecting a PDF is free here and needs no account. Upload your file, choose a password, and download the encrypted copy.

What encryption does this tool use?

The file is encrypted with 256-bit AES (AES-256), the standard used for strong PDF passwords. The protected file cannot be opened without the password.

Can I remove or recover the password later?

If you know the password, you can remove it later with the Unlock PDF tool. If you forget the password, it cannot be recovered, so keep a safe copy of it.

Do permission restrictions fully prevent copying or editing?

No. Permission restrictions are respected by most PDF apps, but some software can ignore them. The password to open the file is the strong protection.