How to Password Protect a PDF (and What It Actually Protects)

Adding a password to a PDF takes thirty seconds. Understanding what it actually protects takes a couple of minutes — and saves a lot of false confidence.

Add a password in three clicks

1. Open Protect PDF.
2. Upload your file and choose a strong password.
3. Download the encrypted PDF.

What "password protected" actually means

Modern PDFs use AES encryption. With a strong password, the file's contents are unreadable without the key — including by us. If the password is lost, the file is effectively gone.

What it doesn't do

• It doesn't stop someone with the password from copying or sharing the file.
• It doesn't prevent screenshots.
• Owner-only restrictions ("no printing", "no copying") are advisory and ignored by some viewers.

Choosing a strong password

• 16+ characters where possible.
• Mix of letters, numbers and symbols.
• Don't reuse a password from another service.
• Share the password through a different channel from the file itself.

Forgotten the password?

If it's your file and you have the original credentials, use Unlock PDF to remove protection.