PDF Password Lock
Add secure AES passwords to PDFs or strip permissions master passwords.
Select or Drop PDF Document
Add an opening password and restrict printing or text copying.
What is this tool?
Encrypts your PDF documents with a strong password, preventing unauthorized opening, printing, or modification.
How to password protect a PDF
- Select or drag a PDF file into the upload zone.
- Enter a strong user password that will be required to open the document.
- Click 'Protect PDF' to begin the client-side encryption process.
- Download the newly encrypted file.
Key Features
- Client-side 128-bit AES encryption via pdf-lib
- Prevents unauthorized viewing without the correct password
- No file size limits (constrained only by browser memory)
- Instant processing without network delays
Frequently Asked Questions
Can a password-protected PDF be easily bypassed?
No. The tool uses standard AES encryption implemented natively within the PDF structure. The contents are cryptographically scrambled and cannot be read without the password.
Can you recover my password if I forget it?
No. Because encryption happens entirely on your device and the password is never transmitted or saved, it is impossible for us to recover lost passwords.
Privacy First
Document encryption is performed 100% locally in your browser memory. Your PDF file and password are never uploaded, logged, or transmitted across the network.
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