Lock a PDF with a password
Some documents should only open for the people you choose: a contract, a statement, anything personal. This tool adds a password to a PDF using strong 256-bit AES encryption, so it genuinely cannot be opened without it. It is free, with no signup and no watermark.
How it works
- Upload your PDF and choose a password.
- Confirm the password so a typo cannot lock you out.
- Download the encrypted file, which now asks for the password before it opens.
Why this one uses a server
Unlike the other Etoolio PDF tools, encryption cannot be done reliably in the browser, so this tool sends your PDF to our server over a secure connection, encrypts it, returns it, and deletes the temporary files immediately. Your file and password are never stored or logged. We are upfront about this because most of our tools keep everything on your device, and this one, by necessity, does not.
Keep your password safe
Strong encryption cuts both ways: if you lose the password, the file cannot be recovered by anyone, including us. Store it somewhere reliable, such as a password manager. To take a password off a file you can already open, use the Etoolio unlock tool; for a visible marking rather than access control, use the watermark tool instead.