Add Password to PDF
Lock down your documents and restrict access. Encrypt your files client-side, control download access with User passwords, and restrict printing or copying with Owner keys.
Drag & drop your PDF document here
or click to search your machine. Supported files remain 100% private.
Key Features & Capabilities
Zero Server Uploads
Encryption algorithms run 100% inside your browser. No files, passwords, or documents are ever uploaded.
AES-256 Standard
Secure your files with Advanced Encryption Standard (AES) 256-bit keys, the current industry-recommended PDF protocol.
Access Control Keys
Add owner keys to configure fine-grained settings like disabling high-quality prints or blocking raw text copying.
Legacy Compatibility
Optionally fall back to RC4 128-bit standard, ensuring your documents remain readable on very old legacy reader tools.
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Help us improve this tool!
Found a bug, want a new option, or have suggestions for Khmer Unicode formatting? Share your comments and help us improve.