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Protect PDF

Add a password to your PDF with AES encryption.

How it works

Step 1

Upload your file

Drag & drop or click to select your PDF from your device, Google Drive, or Dropbox.

Step 2

Process

Our servers instantly run Protect PDF on your file — no plugins or software required.

Step 3

Download

Your result is ready in seconds. Click download and you're done.

Frequently asked questions

How do I password protect a PDF for free?
Upload your PDF, enter the password you want to set, and click 'Protect PDF'. Download the encrypted file — anyone opening it must enter the password.
What encryption does the tool use?
PDFs are encrypted with AES-128 or AES-256 — the same standard used by banks and government agencies. This cannot be bypassed without the correct password.
Can I add editing restrictions without an open password?
Yes. Set permissions restrictions (printing, copying, editing) independently from the open password. Recipients can open the file freely but cannot perform restricted actions.
How do I password protect a PDF in Google Drive?
Google Drive cannot add password encryption to PDFs natively. Download the PDF from Drive, use the Protect PDF tool to encrypt it, and re-upload to Drive.
What makes a strong PDF password?
Use 12+ characters combining uppercase, lowercase, numbers, and symbols. Avoid common words, names, or dates. Store it in a password manager — PDF passwords cannot be recovered if forgotten.
Does adding a password to a PDF affect quality or content?
No. Only the encryption layer is added. All text, images, fonts, and formatting are completely unchanged.