Lock PDF with Password Online Free

PDF password protection exists in two flavors, and most people don't realize they're using the wrong one for their needs. There's the "user password" that prevents anyone from opening the file without the password - total lockdown. Then there's the "owner password" (also called permissions password) that lets people open and view the PDF but restricts what they can do - printing, copying text, editing, etc. Choosing the right protection type depends on your actual security requirement. Our Lock PDF tool offers both options with clear explanations of what each does. You can set a password to completely lock the file, set permissions to restrict actions while keeping the file viewable, or use both for maximum security. The encryption uses industry-standard 128-bit or 256-bit AES encryption, which is the same level banks use. One mistake we see constantly: people password-protecting files then forgetting the password. If that happens with a strong password, the data is essentially unrecoverable. Save your passwords in a password manager.