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Protect PDF

Add password protection to your PDF

Protect PDF — encrypt with a password, free

Password protect your PDF online for free to keep sensitive information confidential. Our protect PDF tool encrypts your document with a password so only the people you choose can open it — ideal for contracts, financial records, and private files, with no watermark and no signup.

Add a user password to control who can open the file and an owner password to restrict editing, copying, or printing. Files are encrypted in transit, processed securely, and deleted automatically afterwards.

How to protect pdf

  1. 1

    Upload your PDF

    Drag and drop the PDF you want to secure, or click to select it from your device.

  2. 2

    Set a password

    Enter the password you want to require to open the document, plus any permission restrictions.

  3. 3

    Protect the PDF

    Click Protect PDF and your document is encrypted with the password you chose.

  4. 4

    Download the secured PDF

    Save the password-protected file. Your original upload is deleted automatically.

Why use our protect pdf tool?

Strong encryption

Your PDF is encrypted so its contents stay confidential without the password.

Control permissions

Restrict editing, copying, and printing with a separate owner password.

Keep sensitive data safe

Perfect for contracts, invoices, and personal documents you need to protect.

Free & no registration

Password protect PDFs online free with no signup and no watermark.

Protect PDF — frequently asked questions

How do I password protect a PDF for free?+

Upload your PDF, set a password, and click Protect PDF. The encrypted file downloads instantly at no cost.

How do I encrypt a PDF?+

Our tool encrypts your PDF automatically when you add a password, so its contents can't be opened without it.

How do I stop people from editing or printing my PDF?+

Set an owner password with permission restrictions to prevent editing, copying, or printing.

How do I add a password to a PDF without Adobe?+

Just use this browser-based tool — no Adobe Acrobat or installed software required.

Is it safe to password protect a PDF online?+

Yes. Files are uploaded over encrypted HTTPS and deleted from our servers automatically after processing.