How to use the password protect PDF
- Select a PDF.
- Type a password twice. Optionally block printing, copying or editing.
- Tap Protect PDF and download the locked file.
Questions
How strong is the protection?
Files are locked with AES-256, the strongest standard in PDF. A long password (10+ characters with letters and numbers) cannot realistically be guessed.
What if I forget the password?
We never see or store your password, so we cannot recover it. Keep an unlocked copy or note the password somewhere safe.
What do the restrictions do?
They tell PDF readers not to allow printing, copying text or editing unless someone enters the owner password. Most readers respect them, but they are a weaker kind of protection than the open password.
The PDF must open on a very old phone or reader.
Turn on "Compatible with old PDF readers" to use AES-128, which works in readers from 2006 onwards.