Guides · Working safely

How to lock a PDF file with a password

With PDF24 Creator you can lock a PDF with a password in under a minute, without uploading it anywhere. Choose a good password and send it to the recipient separately.

Illustration: translucent glass pages sealed by a ring of light
PDF24

Why do you need another program?

In Adobe Acrobat, locking a PDF with a password is only available in the paid business edition, and most offices run the free version. PDF24 Creator is free, also for business use, works directly on your computer and can be downloaded from the official site, pdf24.org.

Download

Where do you download it?

Download PDF24 Creator from the official site only, using the button below. It installs like any other program.

SrvIT customers: we can install it for you remotely, without interrupting your work. Just ask :)

Step by step

Seven steps, under a minute

  1. Open PDF24

    Open PDF24 Toolbox from the desktop icon, or type PDF24 in the Start menu and choose "PDF24 Toolbox". On the main screen, click "Protect PDF".

    PDF24 start screen with the "Protect PDF" tile marked
  2. Choose a file

    Click the orange "Choose files" button. You can also drag the file into the dashed frame. PDF24 works offline, so the file stays on your computer.

    The "Choose files" button marked
  3. Select and open

    Select the file (1) and click "Open" (2).

    File dialog: the file selected and the "Open" button
  4. Type a password and lock

    Type a password in the "User password" field (1) and click "Protect PDF files" (2). You can leave the other fields as they are.

    The password field and the "Protect PDF files" button marked
  5. Save

    When PDF24 says the job is done, click "Save".

    The "Save" button marked
  6. Give it a new name

    Give the file a new name, for example add "locked" to it (1), so you also keep the original without a password. Then click "Save" (2).

    Save dialog: a new file name and the "Save" button
  7. Check that it is locked

    That's it. Anyone who opens the locked file is asked for the password before they can see what is inside.

    A password prompt when opening the locked file
Good to know

Send the password in a separate message or by phone, not in the same email as the file. Keep the password somewhere safe: without it you will not be able to open the file either, and there is no way to recover it.

Need a hand?

If PDF24 is not installed on your computer or something does not work, get in touch. SrvIT customers can ask us to install it remotely.