User Guide



Add a password to a document. This encrypts the document so that it can only be viewed or opened by a user with the password.

Set a document password

  1. Open a document and tap “Tools”  > “Encryption”
  2. Select a level of encryption, details below.
  3. Type a password and verify it, then tap “Done.”


If you own 1Password, while in the password field you will see the 1Password icon. To use 1Password to create your password:

  1. Tap the 1Password icon in the password field.
  2. In the menu which appears, tap 1Password. The 1Password app will open, you will need to login. You can pick the username and password, or have one generated. The name of the document will be kept in 1Password, along with the generated password.
  3. Tap Done, and Done to lock the document.

To unlock a document with 1Password:

  1. Tap on a locked document in Files view.
  2. A password dialog will open. Tap the 1Password icon.
  3. Login to 1Password. You will see the stored login for that document. Tap it to open the document.


Select an encryption level while setting the document password. While stronger encryptions are harder to break, fewer PDF viewers and editors are capable of supporting them. A user with older PDF viewing software may not be able to view your document, even with the password. There are three levels of encryption.

  • Weak: RC4–40 level encryption. A document secured with this level of encryption can be viewed by most PDF viewers.
  • Strong: AES–128 level encryption. A more secure encryption, but can be deciphered by fewer PDF viewers.
  • Strongest, Least compatible: AES–256 level encryption. One of the latest and most secure encryptions. It can only be viewed by PDF viewers which have been updated to support it.
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