macOS · Device Backups
A backup of a phone
you no longer own.
Local device backups are frequently the largest single item inside System Data, and they are invisible in the storage bar. Several generations of them can accumulate — a phone from 2019, an iPad someone in the household replaced — each one tens of gigabytes, none of them ever offered for deletion.
Free to try, no account required.
Why they are hard to find and easy to break
They live somewhere you will never browse to
Under ~/Library/Application Support/MobileSync/Backup, in a Library folder Finder hides by default, in directories named after device identifiers rather than after devices. Nothing about that path is discoverable.
The storage bar files them under System Data
So the largest thing on the disk is inside the one category macOS refuses to explain. People spend an evening clearing caches to recover 3 GB while 80 GB of backups sits untouched.
A backup folder is not just a folder
Finder maintains an index of what backups exist. Dragging a backup directory to the Trash can leave that index referring to something that is no longer there — which is how you end up with a backup that appears in the list and cannot be restored.
Encrypted backups fail quietly rather than loudly
An encrypted backup you no longer have the password for is unusable, and it still occupies the space. It looks exactly like a working one from the outside.
Doing it properly
Delete backups through Finder, not the filesystem
Open Finder, select your device, choose Manage Backups, and delete from there. It removes the files and updates the index in one step. This is the correct method and no third-party tool improves on it — including this one.
Find out what you have first
VaultSort’s storage breakdown sizes the MobileSync directory and everything beside it, so you can see how much is there and how many generations before deciding what to keep.
Then find what else was hiding in System Data
Backups are usually the largest item and rarely the only one. Old iOS software updates, virtual machines, disk images and a forgotten Xcode installation turn up in the same scan.
The large files, ranked
Once the backups are gone, this is the fastest remaining step — a dozen large files typically outweigh a thousand small ones.
Caches, by category and consequence
Browser, developer, media and application caches, sized before anything is removed and rated by what clearing them costs you.
Overwrite the space afterwards, if it mattered
A device backup is a copy of a phone. Deleting one leaves its contents on the disk until something reuses the blocks — so if that is a concern, overwrite the free space once the backups are gone.
What it does not do yet
- — VaultSort does not delete device backups. It finds them and sizes them; Finder’s Manage Backups is the correct way to remove one, and building a shortcut around that would risk leaving the backup index inconsistent.
- — It cannot tell you which backup belongs to which device — those directories are named by device identifier. Finder can, because it holds the pairing records.
- — iCloud backups are not local files and are not touched by any of this. Manage those in System Settings under your Apple Account.
- — System-level cleanup needs the privileged helper installed. Everything described here is user-level and works without it.
Questions people ask
Is it safe to delete an old iPhone backup?
If the device is gone, or you have a current iCloud backup, yes. Check what you have before deleting the only copy: a local backup is the only place some things live if iCloud Backup was never switched on.
Can I just drag the backup folder to the Trash?
It will free the space, and it can leave Finder’s list of backups referring to something that no longer exists. Manage Backups does both halves. Use it — the shortcut saves ten seconds and can cost you a restore.
How much space are they actually using?
Tens of gigabytes each, and there is often more than one. On a Mac with unexplained System Data, this is the first place worth measuring — it is frequently most of the answer.
What about old iOS software updates?
They sit near the backups and can run to several gigabytes. They are safe to remove and re-download if needed, and they show up in the same storage breakdown.
Try it on your own files
One purchase, no subscription. $24.99 once, and every feature is included.