🔒

Protect PDF

Secure your PDF with a password to prevent unauthorized access.

What is Protect PDF?

Password-protecting a PDF prevents unauthorized access without relying on any external service. PDFStream applies 256-bit AES encryption directly in your browser — the original file never leaves your device, and neither does the encrypted version. Set a user password (required to open the document), an owner password (required to print, copy, or edit), or both. After setting the password, download the protected PDF and share it knowing only recipients with the correct password can read it. Practical uses: sending a payslip or tax document by email where you want to control access, sharing a confidential contract with a specific party, distributing a report with sensitive data to a limited audience, or archiving personal records in encrypted form. The protection is standard PDF encryption compatible with Adobe Acrobat, Preview, and all major PDF readers — no proprietary format, no special app required to open the file.

How-to

1
Select File
Upload the PDF you want to protect.
2
Enter Password
Enter and confirm your password.
3
Apply
Click 'Set Password'.
4
Download
Download the protected file.

Practical tips

Store the password safely

Passwords can't be recovered later. Save it in a password manager before sending the protected file.

Restrict editing separately

Use permission settings to block printing, copying, or editing while still letting recipients open the document.

Share the password another way

Send the password through a different channel than the file, such as a message instead of the same email.

🔒

Security

🔓

Unlock PDF

View All PDF Tools →

Frequently Asked Questions

What encryption is used?▼

Standard PDF password protection. It works in all standard readers like Adobe Acrobat.

What if I forget the password?▼

We cannot recover it. Please save it securely.

Can I add to an already encrypted PDF?▼

Unlock it first, then add the new password.

Can I restrict printing?▼

Yes, you can set permissions for printing, editing, and copying.

Do you keep my password?▼

We never see or store your password.

Can I block editing?▼

Yes, editing restrictions can be set.

How strong is it?▼

We use strong AES encryption.

Is it better to use a simple password?▼

No, always use a strong password to prevent attacks.

Does this work on mobile?▼

Yes, the resulting PDF is standard and works everywhere.

Is it secure?▼

Yes, provided your password is strong.

Last Updated: August 6, 2026