macOS has a built-in backup utility called Time Machine that can take periodic backups of your entire system. Much like backups of your iPhone that iTunes can take, a Time Machine backup can help restore your Mac’s files and the entire system to a previous stable state.
Exclude folders Time Machine
By default, Time Machine backs up everything; the entire OS installation, files for every single user configured on the Mac, and the main/system library folder, among other things. All you need to do is set Time Machine up, and it will do the rest.
If you’re taking a Time Machine back up but can do without backing up certain non-essential (or essential) folders, you can exclude them from the backup.
- Click the Apple icon on the menu bar, and select System Preferences.
- Go to the Time Machine preference.
- Click the Select Disk button, and select a disk to create the Time Machine backup on.
- Once a disk has been selected, click the Options… button at the bottom right.
- If you want to exclude system files and applications folders, enable the “Exclude system files and applcations’ option, and click Save.
- To exclude other folders, click the Plus button at the bottom of the ‘Exclude these items from backups’ panel.
- In the folder selection box that opens, navigate to the folder that you want to exclude, and select ‘Exclude’.
- Repeat for all folders that you want to exclude.
- Click Save.
- When you next take a Time Machine backup, the blacklisted folders will not be included in it.
The following limitations apply to a Time Machine backup if you choose to exclude folders from it.
- If you choose to exclude system folders, the Time Machine backup will only be good for restoring your files but will not be able to help you if the macOS installation has been corrupted. You will have to first fix a corrupt macOS installation, and/or install it fresh before you can get your files back.
- Time Machine backups are taken incrementally; the new back up does not replace an older backup. When you exclude a folder from a backup, it will be excluded from the new back up, and not the old one.
- You can exclude any folder of your choice from a Time Machine backup as long as it isn’t a hidden folder.
- If you want to exclude a particular file from a backup, you should add it to a folder of its own, and exclude the folder. All sub-folders under a selected folder are also excluded from a backup.