Where are iPhone backups stored on a Mac?
In ~/Library/Application Support/MobileSync/Backup, which Apple documents. The reliable route is Finder → your device → General → Manage Backups, then right-click a backup and choose Show in Finder or Delete.
Can I delete Time Machine local snapshots?
You can, through Apple’s supported route of briefly pausing automatic backups, but macOS thins them on its own and counts their space as available. Removing them costs a day of recovery points for little lasting gain.
Read the guide: Time Machine local snapshots taking up space on Mac
What happens when the Time Machine backup disk is full?
Time Machine deletes the oldest backups to make room, which is normal. The problem case is a backup that no longer fits at all; exclude rebuildable folders or connect a larger disk.
Read the guide: Time Machine backup disk full: what happens and what to do
Why is iCloud Drive taking up space on my Mac?
Because files you opened or chose to keep downloaded are stored locally as well as in iCloud. Remove Download on a file or folder keeps it in iCloud and frees the local copy; deleting removes it everywhere.
How do I stop Google Drive, Dropbox or OneDrive filling my Mac?
Switch Google Drive to streaming, make Dropbox folders online-only, and use OneDrive’s Free up space. Never delete inside a synced folder to save space; the deletion syncs to the cloud and your other devices.
Read the guide: Google Drive, Dropbox or OneDrive taking up space on Mac
Why is the Photos library so large, and what can I do?
It holds every original. Optimize Mac Storage keeps originals in iCloud and smaller copies on the Mac; moving the library to an external drive keeps every original off the internal disk. Deleting removes photos everywhere.
Read the guide: Photos library taking up space on Mac: what to change
Why is Mail taking up so much space?
Mail keeps local copies of messages and, by default, most attachments. Set Download Attachments to Recent per account, remove attachments from messages you keep, and erase deleted items. Never trim Mail’s folders in Finder.
Read the guide: Mail taking up space on Mac: attachments and old messages
How do I delete Messages attachments on a Mac?
Open a conversation’s details, select the photos or files and delete them, or set Keep messages to 30 days or one year. With Messages in iCloud on, deletions apply to every device, after a 30-day Recently Deleted window.
Read the guide: Messages taking up space on Mac: delete attachments
Can I move the Photos library to an external drive?
Yes; Apple documents the procedure. The drive should be formatted for Mac and stay connected when you use Photos, and you should open the moved library and verify it before removing the original.
Read the guide: How to move your Photos library to an external drive