zip Command on Mac: Rejoined Splits Exit 0 and Are Corrupt
The zip man page on my Mac mini says a split archive "can also be converted into a single-file archive using a split size of 0" and gives the command: zip -s 0 split.zip --out single.zip. I split one 5 MB file into five 1 MB parts, ran that command, and got exit status 0 and a 2.1 MB file. unzip then stopped with invalid compressed data to inflate. The other 2.9 MB were gone, and zip hadn't said a word.
That was one of about 70 runs I made with the zip command on macOS 26 this afternoon, along with unzip, ditto, bsdtar and Archive Utility. Most of what people type after searching "zip command mac" works. The parts that don't usually exit 0, so you only find out when somebody tries to open the file.
The short answer
# zip a folder (without -r you get an empty folder entry and exit 0)
zip -r archive.zip MyFolder
# same, without .DS_Store, .git and other dot files at any depth
zip -r archive.zip MyFolder -x '*/.*'
# from inside the folder, it takes two patterns
cd MyFolder && zip -r ../archive.zip . -x '.*' -x '**/.*'
# password (prompts twice, needs a real Terminal)
zip -er archive.zip MyFolder
# unzip into a folder
unzip archive.zip -d OutFolderApple's /usr/bin/zip reports itself as "Zip 3.0 (July 5th 2008), by Info-ZIP, with modifications by Apple Inc.", and unzip is UnZip 6.00 from April 2009. Apple recompiled both in February 2026, but the code is from 2008 and 2009, and most of the problems below come from that.
Five ways zip -r goes wrong without an error
My test folder had three files, a symlink, a .git folder and a .DS_Store at each of three levels: 12 entries in total. Each command below ran from the folder's parent.
| Command | Exit | Entries | .DS_Store kept |
|---|---|---|---|
zip o.zip proj | 0 | 1 (just proj/) | 0 |
zip -r o.zip proj | 0 | 12 | 3 |
-x .DS_Store | 0 | 12 | 3 |
-x '*.DS_Store' | 0 | 9 | 0 |
-x '.*' | 0 | 12 | 3 |
-x '*/.*' | 0 | 7 | 0 (and no .git) |
-X | 0 | 12 | 3 |
No -r, no warning. zip o.zip proj prints adding: proj/ (stored 0%) and exits 0. You get a zip containing an empty folder.
-x matches the whole stored path. Entries are stored as proj/sub/.DS_Store, so a bare .DS_Store or .* matches nothing. In Info-ZIP's patterns * also matches /, so '*.DS_Store' catches every level.
-X doesn't mean hidden files. It drops extra file attributes (UID/GID and timestamps). It doesn't exclude anything.
Unquoted patterns never reach zip in zsh. zip -r o.zip proj -x *.DS_Store failed with zsh:1: no matches found: *.DS_Store and exit 1 before zip started, because zsh expanded the glob itself and found no match in the current folder. The same thing happens to any unquoted pattern, and I covered it in zsh: no matches found.
Rerunning zip -r never deletes anything. I zipped the folder, deleted sub/b.txt, and ran the same command again. The archive still had b.txt. zip -r -FS ("file sync") took it out.
The 123-vote answer leaves the top-level .DS_Store
The accepted answer on Ask Different's question about zipping without .DS_Store and __MACOSX (158,835 views) says to cd into the folder and run zip -r dir.zip . -x '**/.*' -x '**/__MACOSX'. I ran exactly that inside my test folder. It removed the two nested .DS_Store files and kept the top-level one, plus .git/ and .git/HEAD. Run from inside, top-level paths have no slash in front of them (.DS_Store, not ./.DS_Store), and **/ needs one. Adding -x '.*' fixed it: -x '.*' -x '**/.*' left only the six real entries.
Finder's Compress command is a different thing: it runs ditto -c -k --sequesterRsrc --keepParent, which is where __MACOSX folders come from. Command-line zip never creates them. I measured what each method keeps in the ditto command on Mac.
Passwords: what -e and -P actually give you
Apple's zip can only write the original PKWARE password encryption ("ZipCrypto"), and four things about it matter:
zip -eneeds a terminal. In a script or over a pipe it exited 16 withInvalid command arguments (stderr is not a tty)and wrote nothing.zip -P passwordworks anywhere and shows the password to anyone who runs ps. While a 3 GB job ran,ps -axo argsshowedzip -q -P sekrit-pw z.zip -. The man page puts it in capitals: "THIS IS INSECURE!"- File names and sizes aren't encrypted.
unzip -llisteda.txtand its 24,000 bytes without asking for the password. AES zips also leave names readable. - The cipher is broken. bkcrack implements Biham and Kocher's 1994 known-plaintext attack. Its readme says the attack needs "at least 12 bytes of known plaintext", which a standard file header can provide.
If the password actually needs to protect the contents, make the archive somewhere else. bsdtar, which ships with macOS, wrote AES-256 zips for me with bsdtar --format zip --options zip:encryption=aes256 --passphrase '…' -cf out.zip folder. That still puts the passphrase on the command line, and Apple's unzip can't open the result (see the table below). An encrypted disk image made with hdiutil avoids both problems.
What macOS can unzip, by method
I built 11 test zips with Python 3.14's zipfile module, bsdtar and zip itself, each holding the same 24,000-byte text file, and extracted each one with the four extractors that come with macOS. The method numbers are from PKWARE's APPNOTE.
| Zip contents | unzip | ditto -x -k | bsdtar | Archive Utility |
|---|---|---|---|---|
| Deflate (8), Store (0) | OK | OK | OK | OK |
| bzip2 (12) | 81: need PK compat. v4.6 (can do v4.5) | 1: Unknown compression type | OK | OK |
| LZMA (14) | 81: v6.3 | 1 | OK | OK |
| Zstandard (93) | 81: v6.3 | 1 | 1, plus a 24,000-byte file of zeros | nothing extracted |
| ZipCrypto password | OK with -P | 1 without --password | OK | asks for password |
| AES-128 / AES-256 (99) | 81: unsupported compression method 99 | 1 | OK | asks for password |
| Korean file name, UTF-8 | OK | OK | OK | OK |
| Korean file name, CP949 (old Windows) | 50: Illegal byte sequence | OK | 1 (OK with --options hdrcharset=CP949) | OK |
| 70,000 entries | 7.9 s | 10.1 s | 5.2 s | not tried |
| One 4.5 GB file (Zip64) | OK, 8 s | OK, 2 s | OK, 2 s | not tried |
The bsdtar row is the one to look out for. On the zstd zip, and again on an AES zip with the wrong password, it exited 1 but left a full-size a.txt made entirely of zero bytes. A script that only checks whether the file exists will carry on with it. Apple's bsdtar is built without zstd, which I also ran into with tar on Mac.
Archive Utility got the same files through open -g -a "Archive Utility". For the three encrypted zips the system log showed a text-input field opening, which is the password prompt. My Mac mini runs headless, so I couldn't type a password into it, and I haven't tested whether it decrypts AES. On the zstd zip it extracted nothing and stayed open. ditto --password with no terminal attached was worse: it sat for five minutes without any output until I killed it.
Large files weren't a problem. Zip64 support is compiled into both tools, and the 4.5 GB file went through all three command-line extractors.
Split archives: zip -s 0 truncates, exit 0
zip -s 1m splits an archive into .z01, .z02 … plus a final .zip. That's the accepted answer on "How can I compress a folder into multiple zip files?" (146,660 views). None of the macOS extractors can read the split set: unzip exits 2, ditto says Couldn't read PKZip signature, bsdtar says Unrecognized archive format. So you rejoin it first with the man page's zip -s 0, and that's where the data loss happens.
I ran eight configurations and found the condition. When no file in the archive spanned more than two parts, the rejoined archive was complete, even with three or five parts in total (30 files of 100 KB, for example). Whenever one file spanned three or more parts, the output stopped at exactly two parts' worth of bytes: 2,097,322 bytes with 1 MB parts and 4,194,474 with 2 MB parts. A 2.1 MB file in three parts lost only its last 3 KB, which is enough to make the file fail to extract. Every join exited 0.
That's the case splitting is usually for: one big file that won't fit as an email attachment or under an upload limit. To find out whether Apple's changes were responsible, I installed Homebrew's unmodified Info-ZIP zip 3.0. It truncated the same way, and so did each tool rejoining the other's split. I found no report of this in two searches, and the man page gives the command without any warning.
What did work was joining the bytes myself and letting bsdtar read the result:
cat archive.z01 archive.z02 archive.z03 archive.z04 archive.zip > whole.zip
bsdtar -xf whole.zip # exit 0, byte-identical in my 5-part test
unzip -t whole.zip # warns and exits 2, but its copy was identical tooList the parts in order with the .zip part last. If the archive is for someone else, don't split it with zip. Send one file, or use a format whose tools you've tested on the receiving end.
On Ask Different, I pulled all 112 questions with "zip" in the title from the Stack Exchange API. They have 1,046,464 views between them. Split and multi-part archives account for 11 questions and 192,317 views. Hidden files and __MACOSX account for 6 questions and 178,595 views. Passwords and encryption: 5 questions and 13,721 views. The largest group, 14 questions and 383,484 views, is "can't open this zip" errors, and the extraction table above covers some of those. For which metadata survives each zip method, see Apple Archive vs zip.
FAQ
How do I zip a folder on Mac using Terminal?
Run zip -r archive.zip FolderName from the folder's parent directory. The -r is required: without it zip stores only an empty folder entry and still exits 0. To leave out .DS_Store and other dot files at every level, add -x '*/.*' and keep the quotes, because zsh would otherwise expand the pattern itself and stop with "no matches found".
How do I password protect a zip file on Mac from the command line?
Run zip -er archive.zip FolderName and type the password at the prompt. It needs a real Terminal; in a script, zip -e exits 16 with "stderr is not a tty". The -P option works in scripts but shows the password in ps output. Both use the legacy ZipCrypto cipher, which known-plaintext attacks break, and the file names stay visible. For real protection, use an encrypted disk image or a tool that writes AES.
How do I combine split zip files on Mac?
The documented command is zip -s 0 archive.zip --out whole.zip, but in my tests it silently truncated the archive whenever a single file spanned three or more parts, while still exiting 0. Concatenating the parts in order (cat archive.z01 archive.z02 archive.zip > whole.zip) and extracting with bsdtar -xf whole.zip produced a byte-identical file. Check the result with unzip -t or a checksum before you delete the parts.
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How this was tested: Mac mini (Mac16,10), macOS 26.4.1, Apple zip 3.0 and UnZip 6.00 (both built February 21, 2026), ditto, bsdtar 3.5.3 with libarchive 3.7.4, and Archive Utility opened with open -g -a, all run as a normal user from a launchd agent rather than Terminal, with no locale set (setting LANG to en_US.UTF-8 or ko_KR.UTF-8 didn't change the file-name results). The 11 test zips came from Python 3.14's zipfile, bsdtar and zip -P. The split tests used random data so nothing compressed. Homebrew's Info-ZIP zip 3.0 was installed for the comparison and removed afterwards. The Ask Different numbers cover every question with "zip" in the title that the Stack Exchange API returned on October 13, 2026. For copying files with their metadata instead of archiving them, see ditto.