ALLYX ONE
100% browser-based · zero uploads

PDF Password Protect

Lock any PDF with a password in seconds — free, no account needed, and your file never leaves your device. Set a user password to restrict access, control print and copy permissions, then download the protected file instantly.

Drop your PDF here, or browse

PDF files up to 100 MB

How It Works

1

Pick your PDF

Drop a PDF onto the page or click to choose it. Files up to 100 MB are supported — no sign-up required.

2

Set your password

Enter a password and confirm it. Use the advanced options to add a separate owner password or restrict printing and copying.

3

We lock it here

Your PDF is rendered and encrypted entirely on your device — nothing is sent anywhere. The whole process happens inside your browser.

4

Download your result

Download the password-protected PDF straight to your device, ready to share securely.

How to Password Protect a PDF Online

  1. Drop your PDF onto the upload area or click to select it from your device.
  2. Enter a password in the Password field and confirm it below.
  3. Choose an image quality level — 150 DPI is a good balance between clarity and file size.
  4. Optionally expand Advanced options to set an owner password or restrict printing, copying, or editing.
  5. Click Protect PDF and your browser processes the file instantly.
  6. Click Download protected PDF to save the result.

Note: To encrypt your PDF entirely in the browser without sending it to a server, each page is converted to a high-quality image before the password is applied. This means text will not be selectable in the protected file. All visual content, layout, and images are preserved at full quality.

Features

  • Your file stays private: Everything runs in your browser — nothing is uploaded or stored anywhere.
  • No account required: Open the page and start protecting PDFs straight away.
  • User and owner passwords: Set a password to restrict opening the document, and an optional separate owner password to control permissions.
  • Permission controls: Restrict printing, copying, or editing independently when setting an owner password.
  • Three quality settings: Choose 96 DPI, 150 DPI, or 200 DPI to balance file size against visual clarity.
  • Up to 100 MB: Handles large multi-page documents.
  • Works everywhere: Compatible with Adobe Acrobat, Preview, Chrome PDF viewer, and all major PDF readers.

Frequently Asked Questions

Is my PDF uploaded to your servers?

No. Your file never leaves your device. Everything runs in your browser using JavaScript — nothing is sent to or stored on any server.

Is this free to use?

Yes, completely free. No account required, no hidden charges, and no watermarks are added to your protected PDF.

What is the difference between a user password and an owner password?

The user password (open password) is required to view the PDF. The owner password (permissions password) controls what recipients can do — such as printing or copying. You can set both, or just the user password.

Will text still be selectable in the protected PDF?

Because everything runs in your browser without server access, each page is rendered as a high-quality image before encryption is applied. This means text won't be selectable in the output. All visual content and layout are preserved at full quality.

Which PDF readers will recognise the password?

The output PDF uses standard AES encryption that is recognised by all major PDF readers — including Adobe Acrobat, macOS Preview, Chrome's built-in viewer, Foxit, and others.

How large a PDF can I protect?

Up to 100 MB per file. Processing time depends on your device's speed and the number of pages — large documents with many pages may take a minute or two on slower devices.