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What is Protect PDF?
Password-protect your PDF documents to prevent unauthorized access. Add encryption to sensitive documents like contracts, financial reports, and personal files.
Key Features
How to Use Protect PDF
Upload your PDF
Set a password
Choose permissions
Download the protected PDF
Common Use Cases
Tips & Best Practices
Use strong passwords with mixed characters
Store your password securely — it cannot be recovered
Use owner password for permission-only restrictions
Frequently Asked Questions
How strong is the encryption?
We use AES-256 encryption, the same standard used by governments and financial institutions.
Can I set different permissions?
Yes! Control whether users can print, copy text, edit, or annotate the document.
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Protect PDF is part of our Documents tools collection at AllInAOne. Use our free online tools for all your documents needs — no registration required.