Multi-part archives on macOS
You have a folder that looks like this:
holiday-photos.part01.rar
holiday-photos.part02.rar
holiday-photos.part03.rar
or this:
backup.rar backup.r00 backup.r01 backup.r02
That is one archive, split across several files. You don’t extract them one at a time and you don’t join them by hand — you open the first part and the tool finds the rest.
How to open one
- Put every part in the same folder. This is the step people miss. The extractor discovers the other parts by looking next to the one you opened.
- Open the first part only. For
.partNN.rarthat’spart01. For the legacy scheme it’s the plain.rar, not.r00. For.7z.001sets it’s.001. - Purrchiver sorts the sequence, treats it as a single logical archive, and lists the contents. Extract all of it, or drag out one file.
Point Purrchiver at any part and it will still find the set — but the first part is the reliable habit.
The schemes you’ll actually meet
| Scheme | Looks like | Open this one | Came from |
|---|---|---|---|
| Modern RAR | a.part01.rar, a.part02.rar | part01 | WinRAR 3+ |
| Legacy RAR | a.rar, a.r00, a.r01 | a.rar | Older WinRAR / DOS RAR |
| 7-Zip split | a.7z.001, a.7z.002 | .001 | 7-Zip split volumes |
| ZIP split | a.zip, a.z01, a.z02 | a.zip | Older ZIP tools |
| Byte-split tar | a.tar.001, a.tar.002 | .001 | split on a plain .tar |
The legacy RAR scheme is the one that confuses people most, because .r00
sorts first alphabetically but is the second part. The plain .rar is the
first.
When it fails
“Missing part” / extraction stops partway. A split archive needs every
part. If part03 never finished downloading, nothing after it can be
recovered — the data genuinely isn’t there. Check that each file’s size looks
right; a truncated part is usually obvious next to its siblings.
Parts in different folders. Move them together.
You only have .r00 and up, no plain .rar. The first part is missing.
Some content can sometimes be salvaged from later parts, but not reliably.
Renamed parts. If someone renamed them, the sequence breaks. Restore the original numbering.
Making your own
Purrchiver also creates split-volume sets — pick a format in the Create Archive sheet and set a part size. Useful when you’re up against an attachment limit, a filesystem that chokes on large files, or an upload cap.
Purrchiver writes split ZIP, 7z, and tar sets.
It does not write RAR. Nobody but WinRAR does — RarLab’s license forbids third-party tools from creating RAR archives, which is why every Mac archiver reads RAR and none of them write it. If you need to send a split archive, use ZIP for maximum compatibility or 7z for better compression.
Creating split ZIP and tar sets is free. 7z creation is part of the one-time $9.99 unlock.
A note on what these are for
Multi-part archives are a solution to a 1990s problem — floppy disks, then CD-Rs, then email attachment ceilings. Most of the ones you encounter today arrived from someone working around a 25 MB mail limit, or from a download that was chunked years ago and never reassembled.
If you’re choosing for yourself today, a single archive plus a file-transfer link is almost always simpler. Split volumes are worth it when the receiving end genuinely can’t take one big file.
Get Purrchiver on the Mac App Store →
Related
- Multi-part archives help topic — the in-app reference, including creating split sets
- .sit, .sitx, and .hqx files — the other thing old backups are full of
- Format support — the complete read/write matrix
- Benchmarks — measured speed and ratio for every format Purrchiver writes