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Protect PDF

Encrypt a PDF with a password so it can only be opened by authorised recipients. Processed entirely in your browser.

GuestGUEST

10 uses remaining

Drop a PDF here or browse

One PDF file · Max 40 MB · for higher limits

What is Protect PDF?

Protect PDF encrypts your document with a password using the PDF Standard Security (RC4-40) algorithm. Once protected, anyone who tries to open the file will be prompted for the password you chose. The encryption runs entirely in your browser — your file is never uploaded to any server.

How It Works

Upload a PDF, enter a password, then click Protect & Download. The tool applies PDF standard encryption (RC4 40-bit, the universal format supported by every PDF reader including Adobe Acrobat, Preview, Chrome, and mobile apps). The protected PDF downloads automatically. Share it and give the recipient the password separately.

Key Benefits

  • 100% browser-based — your PDF never leaves your device
  • Generates a universally compatible password-protected PDF
  • Works in Adobe Acrobat, Preview, Chrome, and all mobile PDF apps
  • Prevents unauthorized access with a password of your choice
  • Free to use with no account or registration required
  • Works on desktop and mobile browsers

Frequently Asked Questions

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