Protect & Encrypt PDF Online
Protect your PDF files online for free. Add open passwords, restrict printing, copying, and modifications using industry-standard AES-256 encryption. 100% private in-browser security.
Click or drag files here to upload
Supports batch upload · Max 100MB per file · PDF only
How to Password Protect a PDF?
Upload PDF
Click to select or drag and drop your PDF file into the upload box.
Set Password
Enter a strong open password and configure optional printing and copying restrictions.
Encrypt
Click "Protect PDF" to instantly encrypt the document via WebAssembly QPDF.
Download
Your password-protected PDF will automatically download to your device.
Frequently Asked Questions
What encryption standard is used?
We utilize standard AES-256 bit encryption, the industry benchmark used by financial institutions and defense organizations.
Are my password and files stored anywhere?
Never. Everything runs purely client-side inside your browser. No files, passwords, or data are ever transmitted to any server.
What if I forget the password?
Because AES-256 encryption is mathematically unbreakable without the key, please make sure to store your password in a safe place.
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