Protect PDF Online Free
Protect PDF files by adding password security with BuBird PDF Studio. Use this tool to help prevent unauthorized opening or editing of documents.
How to use this tool
Step 1
Select the PDF file you want to lock and encrypt.
Step 2
Enter a strong, secure password.
Step 3
Choose whether you want to prevent copying or printing if supported.
Step 4
Click Protect PDF to apply password encryption.
Step 5
Download the locked, secure PDF document.
Why choose BuBird
Password Encryption
Encrypts the PDF using standard security protocols to prevent unauthorized access.
In-Browser Security
All encryption operations are executed locally inside your browser.
Universal Lock
Locks files so they require passwords on all PDF viewers (Acrobat, Chrome, iOS).
Common use cases
Secure Personal Files
Lock tax returns, bank records, and personal identification documents.
Business Confidentiality
Protect financial sheets, price quotes, or employee contracts before emailing.
Student Work Protection
Lock essays or dissertation drafts to prevent copying.
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