Protect PDF

Lock a PDF with a password only you share.

Anyone opening this PDF will need to type this password.

    Runs in your browser. Your files never leave your device.

    How to protect a PDF

    1. Drop your PDF files here.
    2. Type the password you want to require.
    3. Download the password-protected PDFs.

    How the password protects the file

    The password you set becomes the file's open password: the encryption locks the whole document, not just certain actions, so a PDF reader cannot show a single page without it.

    Encryption runs with AES-256, the same method used by desktop tools like Adobe Acrobat, and it happens on your device using qpdf compiled to WebAssembly. Nothing about the file or the password is sent anywhere.

    Choosing a password you will not lose

    • Use a password you already know or one saved in a password manager. There is no way to recover it if it is forgotten, here or anywhere else.
    • Mix letters, numbers and a symbol rather than a single common word, especially for anything sensitive.
    • Share the password through a different channel than the PDF itself, such as a text message instead of the same email thread.

    When to protect a PDF

    • Tax documents, pay stubs or bank statements before emailing them.
    • Medical records or forms that include a patient's personal details.
    • Contracts or offer letters that should only be opened by the intended recipient.

    Protect PDF FAQ

    What happens if the password is forgotten?

    There is no way to recover it, here or anywhere else. Store the password somewhere safe before you share the file.

    Is my PDF uploaded to add the password?

    No. The encryption happens inside your browser using the same AES-256 method as desktop PDF software, and the file never leaves your device.

    Will the password work on phones and other PDF readers?

    Yes. AES-256 password protection is a standard PDF feature supported by Adobe Acrobat, Preview, and most PDF apps on Windows, Mac, iPhone and Android.

    Can I protect several PDFs with the same password at once?

    Yes. Drop them all in, type the password once, and download them individually or as a ZIP.

    What is the difference between my password and an owner password?

    The password you type is the open password: without it, nobody can view the file at all. The tool also sets a separate owner password behind the scenes, using a random value you never see, so your open password is the only one that matters.

    Can I remove the password later?

    Yes. Use Unlock PDF here with the same password to get back a plain, unencrypted copy.

    Does protecting a PDF also shrink its file size?

    No. Protect PDF only adds encryption. Use Compress PDF separately first if you also want a smaller file.

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