256-bit Encryption
Lock PDF with Password — Free Online
Password protect your PDF files online for free. Encrypt and secure sensitive PDFs instantly with DocDesk. No sign-up required.
Use Lock PDF with Password Free 100% Free No sign-up needed Instant processing
How to Lock PDF with Password in 3 Steps
- 1
Upload PDF
Upload the PDF file you want to password protect.
- 2
Set password
Enter the password you want to use to lock the PDF.
- 3
Download protected PDF
Download your encrypted PDF — only shareable with the password.
Why Use DocDesk?
- 256-bit AES encryption
- Open & permissions password
- Instant protection
- No watermarks
- Files auto-deleted
- 100% free & private
Frequently Asked Questions
- How do I add a password to a PDF for free?
- Upload your PDF to DocDesk's Lock PDF tool, set your password, and click Protect. Your password-encrypted PDF will download instantly.
- What encryption does DocDesk use for PDF passwords?
- DocDesk uses 256-bit AES encryption, the industry standard for PDF security.
- Can I set different passwords for opening and editing?
- Yes. DocDesk lets you set an 'open' password (required to view) and an 'owner' password (required to edit or print).
- Can I lock any PDF regardless of size?
- Yes. DocDesk supports locking PDFs up to 100MB in size.