Protect PDF.
Add password protection to a PDF file. Uses 128-bit encryption. Free, no sign-up — your data stays protected.
Drop files here or click to browsePDF — max 100MB
How to use
Upload a PDF.
Enter and confirm your password.
Click Protect PDF and download the password-protected file.
Frequently Asked Questions
What encryption is used?
pdf-lib uses 128-bit RC4 encryption. This protects casual access — if you need higher security, use dedicated PDF security software.
What if I forget the password?
There is no way to recover a forgotten PDF password with this tool.