Password Protect PDF Free Online (AES-256)

Add AES-256 password protection to PDF files free. Set open and edit passwords, control printing and copying permissions. No signup, no watermark.

Protecting your PDF with a password prevents unauthorized access and controls what recipients can do with your document. Our free Protect PDF tool uses AES-256 encryption — the same standard used by banks and governments — to secure your files with maximum protection. You can set two types of passwords. An open password requires anyone to enter the password before they can view the document. An edit password allows viewing but restricts editing, printing, and copying. You can use one or both depending on your security needs. Permission controls let you fine-tune access beyond passwords. Allow or restrict printing, content copying, form filling, commenting, and document modification independently. For example, you might allow printing but prevent text copying, or allow form filling but prevent any other modifications. AES-256 encryption is virtually unbreakable with current technology. It would take billions of years for the world's fastest supercomputers to crack a single AES-256 encrypted file. This level of protection exceeds the requirements of most regulatory frameworks including GDPR, HIPAA, and SOX. For recurring document protection needs, establish a standard password policy within your organization. Use strong passwords (12+ characters with mixed case, numbers, and symbols) and distribute passwords through a separate channel from the documents themselves. Never send the password and the protected document in the same email.