Upload the PDF
Choose the file to encrypt.
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Protect PDF
Add a password so recipients must unlock the PDF before viewing. Encryption uses qpdf on the server — install qpdf if this tool reports it is unavailable.
- Secure, easy-to-use, no software download
- Files are automatically deleted after processing
- Works on desktop and mobile
Drop PDF here
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Supported: PDF · Max 100 MB
Related PDF tools
How to use Protect PDF
Set a password
Use a strong password and store it safely — we cannot recover it for you.
Download the protected PDF
Share the file and the password through separate channels when possible.
Why use Protect PDF
- Password required to open
- Server-side encryption with qpdf
- Automatic deletion of temporary copies
Privacy for Protect PDF
This tool may upload your file for temporary server processing. Files are stored outside the public web root and deleted automatically after processing. Do not upload confidential documents unless you accept that risk — no online service is 100% secure.
Protect PDF FAQs
Simple answers about this tool
What if I forget the password?
We cannot unlock it for you. Keep a copy of the original unprotected file if you may need it later.
Why did Protect PDF fail?
qpdf must be installed on the server. Check System requirements.
What file types does Protect PDF accept?
This tool accepts: PDF.
Do I need to install software?
No browser plugin is required. Some advanced server tools need programs like LibreOffice, qpdf or Tesseract installed on the host machine.