Whenever you plug your iPhone or iPad into your Mac to charge or sync, macOS may create a complete local backup of your device. While this is great for data protection, each full backup consumes between 30 GB and 90 GB of storage. If you upgraded your iPhone two years ago, the backup of your old device is likely still taking up space on your Mac SSD.
Where macOS Stores iOS Device Backups
Apple stores local device backups in: ~/Library/Application Support/MobileSync/Backup/. Each backup appears as a folder with a long hexadecimal UDID name.
How to Delete Backups via macOS Finder
- Connect your current iPhone or iPad via USB, or open Finder → Settings → General.
- In Finder, select your device from the sidebar.
- Under the General tab, click Manage Backups...
- Highlight the outdated backup from your previous phone and click Delete Backup.
MagicMacCleaner automatically scans the MobileSync directory and highlights orphaned backups from devices that haven't connected in over six months, making cleanup effortless.
Shrink Future Backups: Declutter Your iPhone Storage First
If your local iPhone backups in MobileSync are taking up 50GB to 100GB of Mac SSD space, the fastest way to shrink them is to clean up your iPhone before you sync. When your iPhone is bloated with duplicate 4K videos, massive chat downloads, and unreviewed screenshots, macOS dutifully backs up every single byte of that digital clutter to your Mac drive.
- Clearly Smart Storage Cleaner: Uses on-device CoreML to compress bloated 4K videos down by up to 75% without visible loss of quality, cleans duplicate photos, and merges contact records with one tap.
- Swipe Photo Cleaner: Employs an addictive Tinder-style gesture interface (swipe right to keep, swipe left to delete) to trim thousands of camera roll photos, screenshots, and bursts in minutes.
Pro-Tip: Shrink the Source Before Backing Up
Trimming 30GB of clutter from your iPhone directly reduces future Mac Finder backups by 30GB, freeing double the space across both your devices.
