Password Protect PDF Online
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Sending sensitive financial documents or legal contracts via email without encryption is a major security risk. This tool lets you quickly lock your PDFs with strong 128-bit AES encryption before sharing them.
Client-Side Cryptography
Using the Web Crypto API and a native JavaScript PDF library, the tool reads your document, applies your chosen user or owner password, and encrypts the binary stream. It exports a secure, password-protected PDF directly to your device.
Zero Data Exposure
Because encryption happens natively in your browser's memory, your confidential files are never uploaded to a remote server, ensuring complete privacy.
How to use Password Protect PDF
Upload PDF.
Enter password.
Download.
Example Usage
Sample Input / Output
Enter your secure password.
This shows a sample input and the format you can expect back from password protect pdf.
Frequently Asked Questions
Is it encrypted?
Yes.
Professional Resources & Documentation
Stay updated with the latest industry standards and technical specifications. Our team recommends these authoritative sources for deepening your understanding of password protect pdf and related technologies.
Official history and technical background of the PDF standard.
RFC 3778 - The application/pdf Media Type.
Extensive overview of the Portable Document Format.
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How to use Password Protect PDF
Step-by-step guide, tips, and use cases