Protect PDF with Password Online - Encrypt PDF Free
Password protect your PDF files with strong encryption online. Prevent unauthorized access and viewing for free.
Select PDF file to protect
Add password protection to secure your file
How to Protect PDF Online in 3 Easy Steps
Fast, simple, and processed right inside your browser without queue times.
Select PDF
Upload the confidential PDF file you want to lock.
Set Strong Password
Enter and confirm your chosen document password.
Download Encrypted PDF
Download your locked PDF. It will now require the password to open in any viewer.
Why Use MergPDFOnline for Protect PDF?
Standard PDF Encryption
Compatible with all standard PDF readers including Adobe Acrobat, Chrome, and Apple Preview.
Total Local Privacy
Your password and file are processed locally in your browser — zero password leaks.
Secure Sensitive Information
Protect bank statements, payroll data, and confidential agreements before emailing them to clients or coworkers.
Frequently Asked Questions
100% Privacy Guarantee
Files never leave your device. All computations happen in your web browser.