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How to password-protect a ZIP file on a Mac
By Himanshu Ranjan · Updated 8 November 2026
Select the files in Finder, open FileDial and choose Archive › ZIP with password… Pick Standard (ZipCrypto), which opens in Finder but is weak, or Stronger (AES-256), which needs 7-Zip or The Unarchiver to open. Finder's own Compress has no password option. It all runs offline on your Mac.
Finder cannot do this
Apple's Compress command in Finder has no password option. That is why people end up in Terminal or on a web page that wants an upload, which defeats the point of protecting a file. FileDial adds the option without either.
There are two tools: Archive › ZIP with password… to create a protected ZIP from files or folders, and Protect › Add password… to make a protected copy of an archive you already have.
Standard or stronger
The tool offers two choices, and the note spells out the trade-off. Standard (ZipCrypto) opens in Finder. Stronger (AES-256) needs 7-Zip or The Unarchiver to open.
That trade-off is real security, not a formality. Wikipedia's ZIP article calls ZipCrypto the original scheme and describes it as seriously flawed, vulnerable to known-plaintext attacks. AES, added in the WinZip AE-x format, is the stronger option. Choose Standard only when the recipient must open it in Finder and the content is low-stakes, and choose Stronger for anything sensitive.
- Select the files or folders in Finder.
- Open the dial with the right Option key and choose Archive, then ZIP with password…
- Enter a strong password and pick Standard or Stronger (AES-256).
- Send the ZIP and share the password by a different channel, never in the same email.
Removing or changing a password
Protect › Remove password… makes a new unprotected ZIP beside the original, which you will need once you know the password. To open a protected archive, use Extract › Extract with password…
A password on an archive protects the contents, not the file name or the fact it exists, and a weak password is guessable regardless of the algorithm. Use a long passphrase.
Other file types
A ZIP is not the only option. For PDFs, FileDial has its own password tool, covered in our PDF password guide, and Pages exports Word or PDF with a password you set on the copy. Use whichever protects the format you are sending.
Privacy
Everything runs on the Mac. The password you type is used locally to build the archive and the file never goes to a website.
Choosing a good password and sharing it
Encryption is only as strong as the password. Use a long passphrase of several unrelated words rather than a short complex string, and never reuse one you use elsewhere. 7z derives its AES-256 key from the passphrase by running SHA-256 about half a million times, but Wikipedia still recommends a strong password anyway, because a guessable one defeats any algorithm.
Send the password by a different channel from the file: the ZIP by email, the password by phone or a messaging app. If the same inbox is compromised, the attacker has both. For a one-off share between Macs, Share › AirDrop avoids email entirely, though the password still protects the file if it is forwarded.
Common mistakes and when FileDial fits
The protection covers the content. It does not make the archive invisible, and depending on the tool, file names may be visible to anyone who opens the archive's listing. Treat file names as public if the archive may be intercepted. Also remember that someone with the file can try unlimited guesses offline, which is why standard ZipCrypto is a poor choice for anything valuable.
For sensitive PDFs, a PDF password may be a better fit than a ZIP, because the recipient opens the PDF directly. For anything where the stakes are high, use Stronger (AES-256) and a long passphrase, and tell the recipient which app to use before sending.
Use it when you want a protected archive without Terminal or an upload site. It gives you both options in one place and tells you plainly which opens in Finder and which does not.
Do not use ZIP encryption as your only protection for truly sensitive material. A full-disk or encrypted disk image approach may fit better for files that stay on your own Macs, and Archive › Make disk image (DMG) writes a compressed read-only disk image if you want that shape. For sharing with others, a strong AES-256 ZIP and a separately sent passphrase is a reasonable, practical choice.
Choosing Standard because it is easy to open, and then sending sensitive data, is the first. Sending the password in the same email as the file is the second. The third is using a short, guessable password. The fourth is forgetting that you will need the password later: store it in a password manager, because there is no recovery for a lost AES key. The fifth is protecting a ZIP and leaving the unprotected originals lying around in the same folder.
After sending, delete the loose originals if they are not needed, and keep the protected ZIP as your copy.
Questions
Should I pick Standard or Stronger (AES-256)?
Standard (ZipCrypto) opens directly in Finder, but Wikipedia calls it seriously flawed and vulnerable to known-plaintext attacks. Stronger (AES-256) is far safer but needs 7-Zip or The Unarchiver to open. Use Stronger for anything sensitive, and tell the recipient which app they need.
Can Finder's Compress add a password to a ZIP?
No. Finder's Compress command has no password option, which is why people turn to Terminal or to web tools that want an upload. In FileDial, Archive › ZIP with password… builds a protected ZIP locally, and Protect › Add password… protects an archive you already have.
How do I remove a password from a ZIP I own?
Use Protect › Remove password…, which writes a new unprotected ZIP beside the original. You need to know the current password. The original protected file stays where it is, so you can compare or keep both. To simply open a protected archive, use Extract › Extract with password… instead.