Protect & Unlock PDF

The Protect & Unlock PDF tool adds a password to a PDF so it can't be opened without it, or removes a password from a PDF when you already know it — both processed entirely in your browser, so the password you type and the document itself are never transmitted anywhere. It automatically detects whether a file you upload is already encrypted and switches to the right mode for you. So whether you want to password protect pdf, remove pdf password protection you set earlier, or encrypt pdf online without trusting a third-party server, this is the tool.

Encryption uses the standard PDF security model supported by virtually every PDF reader, applying the password you choose as both the user password (required to open the file) and owner password (which would otherwise control permissions like printing or copying). This isn't the place for protecting state secrets — PDF encryption strength varies by reader and settings — but it's a solid, widely compatible way to keep a casual reader out of a document you don't want freely opened, like a payslip, a personal report or an internal memo.

Unlocking works the other way: give the tool the correct password for an already-encrypted PDF, and it decrypts the document and saves a fresh copy with no password required to open it. If the password is wrong, or the file wasn't actually encrypted to begin with, the tool tells you plainly instead of producing a broken file.