How to password-protect or unlock a PDF
- Choose a PDF, then pick Add password or Remove password.
- To protect it, type the password twice and choose what readers may do. To unlock it, type the current password.
- Press the button and the new PDF downloads.
Write the password down somewhere safe before you send the file. There is no way to reset it.
Questions
Are my PDF and password uploaded?
No. Encryption and decryption run in your browser with a WebAssembly build of qpdf. Neither the file nor the password is sent anywhere.
How strong is the protection?
The file is encrypted with AES-256, the same standard modern PDF readers use. A long password that is not a dictionary word is what keeps it safe. If you forget the password, nobody can recover the file.
Can you remove a password I do not know?
No. You need the password. The one exception is a PDF that opens without a password but blocks printing, copying, or editing: leave the password field empty and those limits are removed.
What do the permission options do?
They tell PDF readers whether to allow printing, copying, editing, and commenting. Most readers follow them, but the open password is the only real lock.
Does it change what the pages look like?
No. The content is copied as it is and only the encryption is added or removed.
Credits
Built on qpdf (WebAssembly build by neslinesli93) (Apache-2.0). OneTooling is not affiliated with that project.