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The user password is required to open the PDF at all. The owner password protects the permission settings and is what someone needs to change or remove them later. Set only an owner password if anyone should be able to open the file but with printing, copying, or editing restricted.

Permission flags are only enforced when an owner password exists; without one, PDF readers treat the file as unrestricted. The tool therefore requires a New Owner Password whenever you set permissions or a user password.

Uncheck "Allow Copying Text" and "Allow Printing", enter a New Owner Password, and click Change Permissions. Adobe Reader and other compliant viewers will then block those actions. Some third-party tools ignore permission flags, so for sensitive material consider rasterizing the pages as well.

Seven checkboxes: printing, copying text, modifying content, annotating, filling forms, document assembly (inserting, deleting, or rotating pages), and page extraction. An unchecked box means the action is not allowed.

The output is encrypted with 256-bit AES. That also makes this a quick way to upgrade an old RC4-encrypted PDF: enter its current password, set new passwords, and the file is rewritten with AES-256.

Yes, enter the existing password in the Current Password field. The tool opens the file with it, then re-encrypts it with your new passwords and permission settings; a wrong current password produces an error and nothing is changed.

Leave both new password fields empty and click Change Permissions. The output is fully decrypted with no passwords and no permission flags. If you don't have the current password, use Remove Restrictions instead, which works without one when the PDF opens freely.

No. The encryption is done by QPDF compiled to WebAssembly inside your browser tab, so the file and every password you type stay on your device.