Protect PDF
Add a password to a PDF with 256-bit AES encryption. Set an open password and an owner password, then download the protected file — no uploads.
Protect PDF
Drop a PDF to protect
or click to browse — PDF only
How to use protect pdf
- 1
Add a PDF
Drop the PDF you want to lock with a password.
- 2
Set passwords
Choose the password required to open the file, plus an owner password for full access.
- 3
Encrypt and download
The PDF is encrypted with 256-bit AES and saved to your device.
What you can do
256-bit AES encryption
Add a real open password using the industry-standard qpdf encryption engine.
Separate owner password
Keep a master password that controls permissions, distinct from the open password.
Runs in your browser
Encryption happens on your device via WebAssembly — your file is never uploaded.
Frequently asked questions
What encryption is used?
The PDF is encrypted with 256-bit AES, the strongest encryption available in the PDF standard.
What is the difference between the two passwords?
The user password is required to open the document. The owner password grants full control and can be different; leaving it the same is fine for most people.
Can I remove the password later?
Yes. Use the Unlock PDF tool with the password to create an unprotected copy.