How to Password Protect a PDF (Free)
Add a password so only the right people can open your PDF — encrypted on your device.
Updated July 2026 · 2 min read Files never leave your device
Quick answer
To password protect a PDF, open Protect PDF, upload your file, choose a strong password, and download the encrypted PDF. It's free and encrypts the file on your device, so nothing is uploaded.
How to password protect a PDF
- 1Open Protect PDF.
- 2Upload the PDF you want to lock.
- 3Type a strong password.
- 4Download your encrypted PDF.
Pick a strong password
- Use at least 12 characters.
- Mix upper and lower case, numbers, and symbols.
- Don't reuse a password you use elsewhere.
Frequently asked questions
How strong is the password protection?＋
Protect PDF uses AES-256 encryption, the same strong standard used by banks and governments.
What if I forget the password?＋
There is no way to recover it. Keep your password somewhere safe, because without it the file cannot be opened.