Secure Protect PDF Tool

Add a strong password to your PDF document to prevent unauthorized access. Everything is processed directly in your browser. No uploads, 100% private.

100% Local Processing

Your document and password never leave this device. Encryption happens securely via JavaScript inside your browser.

Select PDF File

Drag & drop your document here or

How to Password Protect a PDF Online

1

Upload Document

Drag and drop your unprotected PDF file into the secure offline drop zone.

2

Set a Password

Type a strong password. This password will be required by anyone trying to open the file.

3

Download Encrypted

Click encrypt and instantly save your new, highly secure PDF document to your device.

Key Features of Our Protection Tool

  • Absolute Privacy: Your sensitive files and passwords are never uploaded to any server. The encryption happens entirely inside your browser’s memory.
  • Flattened Security: To guarantee maximum offline security, this tool rasterizes your document into layers before applying the password, ensuring text cannot be scraped.
  • Works Offline: Once the webpage loads, you can safely disconnect your internet and lock your confidential documents entirely offline.

Frequently Asked Questions

What happens if I forget my password?

If you forget the password you set, the file cannot be opened. We do not store your passwords or keep copies of your files, so we cannot recover it for you. Please memorize it carefully.

Why can’t I select the text in the protected PDF?

For client-side JavaScript to apply encryption securely, it converts the pages into high-quality visual layers. This adds a double layer of security: it requires a password to open, and prevents unauthorized copying of text.

Can I remove the password later?

Yes! If you know the password, you can use our “Unlock PDF” tool to permanently remove the encryption whenever you need to.

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