How to password-protect a PDF
Published
Payslips, medical reports and bank statements are often sent by email. A password means that if the message reaches the wrong person, or the file is copied somewhere, the contents still cannot be read.
Step by step
- Open Protect PDF and add the document.
- Type a password, then type it again to confirm.
- Choose whether printing and copying text are allowed.
- Press Protect PDF and save the locked file.
- Open it once to check that it asks for the password.
How strong is it?
The file is encrypted with AES-256, the same standard banks and governments use. Without the password the contents are unreadable. The weak point is the password itself, so use at least 12 characters or a few random words, not a name or date of birth.
The print and copy settings are respected by most PDF readers, but they are a request, not a lock. The password is what really protects the file.
Sharing the password safely
Never send the password in the same email as the file. Send it another way, such as a text message or a phone call. Keep a copy of the password, because nobody can recover it for you: the tool never sees or stores it.
Removing a password later
If you know the password and want an unlocked copy, use Unlock PDF. For extra privacy, remove names and numbers first with Redact PDF.