Adding a password to an archive is useful any time you're sending files through a channel you don't fully control — email, cloud storage links, or a shared drive. It won't protect against every threat, but it stops a file from being casually opened by whoever it's forwarded to.

Creating a password-protected archive

  1. Select the files or folders you want to include by tapping the checkbox next to each one in your archive app's file browser.
  2. Tap the "Compress" action, usually found by tapping the first selected item or a menu icon.
  3. Choose the output format. ZIP and 7Z both support password protection; 7Z is the stronger option (see below).
  4. Enter a password in the field provided, and confirm it. Some apps show a strength indicator here.
  5. Start compression. The resulting file will prompt for the password the next time anyone tries to open it, including you.

ZIP encryption vs 7Z encryption

Not all password protection is equal. Classic ZIP encryption is easy to open with cracking tools because of a weakness in the algorithm that's been known for years — it will stop a casual look, but not a determined one. Many modern archive tools instead offer "AES-256" as a ZIP encryption option, which is much stronger, though not every ZIP-compatible program on the receiving end will support it.

7Z's built-in AES-256 encryption is both strong and consistently supported by 7Z-compatible tools, and it has an additional advantage: it can optionally encrypt the list of filenames inside the archive too, not just their contents. With plain ZIP encryption, anyone can see the file names even without the password.

If compatibility matters more than strength: use ZIP with AES-256 if your archive tool offers it as an option, since ZIP still opens on more devices by default than 7Z does.

Choosing a password that survives being forgotten

Archive passwords aren't tied to your phone's lock screen or Google account, so there's no "forgot password" recovery option built into the format itself. If you lose the password, the file is effectively locked forever for practical purposes — brute-forcing a decent password against AES-256 is not something a phone, or most computers, can do in a reasonable amount of time.

A password manager is the simplest fix: generate the password there, save it under a note referencing the archive's filename, and you'll never be stuck guessing later.

Opening a password-protected archive you received

Tap the archive as normal. When your archive app detects encryption, it will show a password field before displaying any contents. If you get a "wrong password" message on a password you're sure is correct, check for trailing spaces or autocorrect changes if you copied it from a messaging app, since a single mismatched character will fail silently rather than telling you which character was wrong.

Once your files are safely archived, if you're doing this as part of moving to a new phone, our guide to backing up installed apps covers packaging app data the same way.