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Protect PDF

Add password protection to your PDF

Drop your file here

or click to browse from your computer

Supported: .pdf • Max 10MB

How to protect pdf

1

Upload your PDF

Select the PDF file you want to protect.

2

Enter a password

Choose a strong password for the document.

3

Click Protect PDF

Password protection is applied instantly in your browser.

4

Download

Save the protected PDF and share it securely.

About Protect PDF

Secure your sensitive PDF documents by adding password protection with PDFNinja. Set a password that recipients must enter before they can open the file. This adds a layer of access control suitable for sharing confidential reports, contracts, and personal documents.

All encryption happens in your browser — the file and password never leave your device, making this the most private way to protect a PDF online.

Features

  • Set open/access password
  • Metadata-level protection
  • Processing done entirely in-browser
  • Password never sent to any server
  • Compatible with all major PDF readers

Frequently Asked Questions