Protect PDF files
Add password protection to your PDF files.
Protecting PDF...
Do not close your browser. Wait until your files are uploaded and processed! This might take a few minutes.
What is Password Protect PDF?
Encrypt and protect PDF documents with strong passwords online for free. Add encryption and restriction settings securely inside your browser.
When should you use it?
This tool is useful when you need to protect, unlock, sign, compare, or permanently remove sensitive PDF information.
Browser-based PDF processing
PdfPix is designed for direct browser workflows. For most tools, files stay on your device during processing, which helps reduce upload delays and supports privacy-focused document handling for everyday PDF tasks.
How to use Password Protect PDF
Upload the PDF file you wish to secure.
Enter and confirm a strong password.
Click 'Protect PDF!' to encrypt the file with high-grade security and download it.
Why choose PdfPix for Password Protect PDF?
100% Secure & Private
Unlike traditional web converters, all processing happens locally inside your browser. Your sensitive PDF files are never uploaded to any remote servers.
No File Size Limits
Because conversions run locally using your computer's CPU power, we don't impose any artificial file size caps, queue delays, or wait times.
100% Free Forever
Get full access to all features without subscriptions, credit card inputs, or registration walls. No branding watermarks added to your outputs.
Universal Compatibility
PdfPix runs smoothly inside any modern browser on macOS, Windows, Linux, iOS, or Android, without needing external applications or plugins.
Frequently Asked Questions
What level of encryption is used?
PdfPix utilizes robust industry-standard PDF encryption algorithms to secure your files.
Does this lock editing and printing?
Yes, password protection blocks unauthorized users from opening, editing, printing, or copying text from your PDF.
Will PdfPix store my password?
No. Since your file is encrypted locally in your browser, we have no access to your password or your files.
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