Protect PDF

Add password protection to your PDF files. Encrypt with 256-bit AES. Free, no signup — files are auto-deleted after processing.

Free No signup Encrypted transfer Under 2 minutes

Drag & drop your file here, or click to browse

Accepts PDF

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This may take a moment. Your file is encrypted in transit and auto-deleted after processing.

How to Protect PDF

  1. 1

    Upload your PDF

    Drag and drop your PDF or click to browse.

  2. 2

    Set a password

    Enter a password to protect your PDF. Optionally set an owner password to restrict editing and printing.

  3. 3

    Download protected PDF

    Click "Protect PDF" to encrypt. Your password-protected PDF downloads automatically.

Frequently Asked Questions

Upload your PDF to ChangeThisFile, enter a password, and click Protect. The PDF is encrypted with 256-bit AES and downloads automatically.

ChangeThisFile uses 256-bit AES encryption, the same standard used by banks and governments. This is the strongest PDF encryption available.

The user password is required to open the PDF. The owner password restricts actions like printing, copying text, and editing — even for someone who can open the file.

Yes. Your file is encrypted during transfer, processed on our server, and automatically deleted immediately after. We never store your files or passwords.

Yes. Use our Unlock PDF tool to remove password protection from any PDF — you just need to know the password.

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Add password protection to your PDF files. Encrypt with 256-bit AES. Free, no signup — files are auto-deleted after processing.

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