What encryption standard is used?

AES-256 encryption per the PDF 2.0 specification — the strongest available PDF encryption standard.

What is the difference between user and owner passwords?

The user password is required to open the PDF. The owner password controls permissions (printing, copying, editing) — it can be set separately from the user password.

Can I restrict printing or copying?

Yes — use the permission checkboxes to control: Print, Copy Text, Edit Content, Fill Forms, Add Annotations, and Assemble Document.

Is the password stored anywhere?

No. Your password is used only in-browser to encrypt the PDF and is never transmitted or stored.

📄 PDF Tool Free · No Upload · No Account

Password Protect PDF Online for Free

Add AES-256 password protection to PDF files. Set user and owner passwords, control permissions (print, copy, edit), and generate strong random passwords.

Files never uploaded No account required Unlimited use, free forever WebAssembly-powered

Drop your file here, or click to browse

PDF to password-protect

Or press Ctrl+V to paste

How to Protect PDF

Upload your PDF

Drop your PDF file into the upload area.
Set your password

Enter a password (or generate a strong random one). Optionally set an owner password and restrict permissions.
Download protected PDF

Click "Protect & Download" — your PDF is now encrypted with AES-256.

Features

AES-256 encryption (PDF 2.0)
User and owner passwords
Permission controls (print, copy, edit, etc.)
Password strength meter
Random password generator
100% client-side — password never transmitted

Frequently Asked Questions

What encryption standard is used?: AES-256 encryption per the PDF 2.0 specification — the strongest available PDF encryption standard.
What is the difference between user and owner passwords?: The user password is required to open the PDF. The owner password controls permissions (printing, copying, editing) — it can be set separately from the user password.
Can I restrict printing or copying?: Yes — use the permission checkboxes to control: Print, Copy Text, Edit Content, Fill Forms, Add Annotations, and Assemble Document.
Is the password stored anywhere?: No. Your password is used only in-browser to encrypt the PDF and is never transmitted or stored.