A password on a PDF stops anyone without it from opening the file, which matters for bank statements, ID scans, contracts and payslips you send by email or WhatsApp. This guide explains the two kinds of password, how to set a good one, and how to remove it later.
How to protect a PDF
- Open Protect PDF and add the file.
- Type an open password. Pick a strong one, and see below.
- Optionally limit printing, copying or editing.
- Download the protected file and test that it asks for the password.
The two passwords
| Password | What it does |
|---|---|
| Open (user) password | Required to view the file at all. This is the real protection. |
| Owner (permissions) password | Controls the printing, copying and editing limits. Without it, those limits cannot be lifted. |
Printing and copying limits are respected by Acrobat Reader, browsers and most apps, but they rely on the reader software. Treat the open password as the lock and the limits as an extra layer.
Choosing a good password
- Use at least 12 characters. Length beats complexity; see the strong password guide.
- Do not use your date of birth, phone number or name. Anyone who knows you can guess these.
- Generate one with the Password Generator and keep it in a password manager.
- Send the password through a different channel than the file, for example the file by email and the password by phone call or SMS.
Removing a password
If you know the password and want an open copy, use Unlock PDF: enter the password and download a file that opens without one. It cannot crack an unknown password, and you should only unlock files you are allowed to open.
Frequently asked questions
Will the protected PDF open on any device?
AES-256 needs Acrobat Reader 9 (2008) or newer, or any current browser or phone. Practically every reader in use today supports it.
Does a PDF password protect the file name or the email?
No. It protects the contents. The file name, and the message you send it in, are not encrypted.