# Protect PDF

> Add password protection to a PDF using the local QPDF encryption engine. The protected PDF requires the open password in PDF readers that enforce PDF encryption.

Canonical: https://helpers.aibrush.co/en/protect-pdf

## Options

Open password required to view the PDF.

Optional separate owner password for PDF permission metadata.

AES-256 or AES-128 encryption strength.

## How to protect a PDF

1. **Upload PDF** — Upload one PDF and wait for local inspection to finish.
2. **Set password** — Enter and confirm the open password. Optionally set a separate owner password.
3. **Pick encryption** — Choose AES-256 unless you need compatibility with an older reader.
4. **Protect and download** — Select Protect PDF and download the encrypted result.

## FAQ

### Is my PDF uploaded?

No. The PDF and passwords stay in your browser.

### Can you recover a lost password?

No. Keep the password somewhere safe before sharing the protected PDF.

### Does this stop screenshots or photos?

No. PDF encryption controls opening the file in readers; it cannot stop someone from capturing what they can view.