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Protect PDF with a Password

Add a password to a PDF before sharing it, using AES-256 encryption that runs in your browser.

Processed on your device
  • AES-256 encryption
  • Opening-password protection
  • Password stays on your device
Works in your browser · Your files stay hereFree · No account · No daily task limit
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How to use Protect PDF with a Password

  1. Drop your PDF.
  2. Choose a password (6+ characters) and confirm it — optionally set a separate owner password.
  3. Download the encrypted copy. Anyone opening it will need the password.

Protect PDF with a Password: your questions answered

How is the PDF protected?

The PDF is encrypted with AES-256 by qpdf running in your browser. Your file and chosen passwords are not uploaded. Use a long, hard-to-guess password: strong encryption cannot make a weak password strong.

What if I forget the opening password?

Omnikit does not keep a copy or offer password recovery. Keep an unencrypted original somewhere safe if appropriate, and store the password securely.

What is an owner password?

It controls changes to PDF security settings. You can choose a separate owner password; otherwise the opening password fills both roles. It is not a signing certificate.

Privacy

This tool runs entirely in your browser. Your file is processed on your device and is not uploaded to a server. You do not have to take that on trust — the monitor directly beneath the tool reads your browser’s own record of every request this tab made while your file was open.

See the full network readout

Keep the good work going.

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