Password Protect & Unlock PDF Files Online — Free & Secure

Password protect PDF files or unlock PDF documents online for free. Add or remove PDF password protection in bulk up to 20MB with secure, browser-based processing. No uploads, no accounts, and no software installation required.

How to Password Protect a PDF Document

Three simple steps to secure your documents

1
📤

Upload your PDF

Drag and drop or click to select your document from your device

2
🔐

Set your password

Choose a strong password to encrypt and protect your document

3
⬇️

Download secured PDF

Get your password-protected PDF file instantly

You can also unlock PDF documents and remove password protection using the same steps.

Powerful Features

Everything you need to secure your PDFs

Lock PDFs

Secure your PDF files with strong password protection and prevent editing, copying, or unauthorized access.

Unlock PDFs

Unlock PDF documents and remove password protection instantly when you have the correct password.

Batch Processing

Process multiple PDF files at once with individual or shared passwords.

Lightning Fast

Process PDFs instantly in your browser with no waiting or uploading.

100% Private

All processing happens locally. Your files never touch our servers.

Works Everywhere

Compatible with all modern browsers on any device or platform.

Why PDF Locker?

PDF Locker was built with a simple mission: to provide the most secure and private way to password protect and unlock PDF documents. In an era of constant data breaches, we believe your files should never have to travel across the internet just to be password-protected.

Our client-side encryption technology ensures that all processing happens directly in your browser. Whether you're a professional handling confidential client data or an individual securing personal documents, PDF Locker gives you peace of mind without the need for expensive software installations.

AES-256 Encryption
Instant Processing

Privacy First

Your files never leave your device. We use local browser processing so your data is 100% private.

No Setup Required

No account creation, no subscriptions, and no desktop software to install. Just open and use.

Universal Compatibility

Works on any operating system with a modern web browser. Desktop, tablet, or mobile.

Trusted by Professionals

"Our sensitive documents need protection. This tool takes seconds to use and gives us confidence that our information stays secure."

RS
Rebecca Singh
HR Consultant

"I secure investor documents before sending them. Professional results without the enterprise software price tag. Highly recommended."

JK
Jennifer Kim
Startup Founder

"Simple, fast, and secure. I use it for all confidential documents before sharing with clients. The browser-based approach gives me complete peace of mind."

MP
Michael Peters
Legal Consultant

Frequently Asked Questions

How do I password protect a PDF for free?

You can password protect a PDF for free by uploading your file, choosing a strong password, and locking the document directly in your browser. No uploads or signups required.

How do I unlock a PDF document?

To unlock a PDF document, upload the file and enter the correct password. The tool will remove the password protection securely in your browser.

Is it safe to process PDFs here?

Yes! All processing happens locally in your browser. Your files never leave your device and are not uploaded to any server.

What encryption level is used?

We use industry-standard AES-256 encryption, the same level of security used by banks and government institutions.

Can I process multiple PDFs at once?

Yes! You can upload multiple files and protect them with either the same password or individual passwords for each file.

Is there a file size limit?

Yes, the maximum file size is 20 MB per file to ensure fast processing in your browser.

Can I unlock a PDF if I forget the password?

No, AES-256 encryption is extremely secure. If you forget your password, the file cannot be unlocked. Keep your passwords safe!

Ready to Protect Your PDFs?

Secure your documents with password protection in seconds. No sign-up required.