How to backup your Mac with Time Machine


macOS includes a built in user friendly backup solution to automatically backup your Mac.

What does Time Machine backup?

Time Machine will backup all of your files, including apps, music, photos, email, documents and system files.

Certain system files that are installed as part of macOS are excluded as they will be restored by reinstalling macOS.

How often does Time Machine backup my Mac?

Time Machine automatically creates hourly backups for the past 24 hours, daily backups for the past month and weekly backups for all previous months. 

Time Machine will automatically delete the oldest backups when your backup disk becomes full.

Where can I backup my Mac using Time Machine?

  • External drive connected to your Mac including USB, Thunderbolt or FireWire drives.
  • External drive connected to an AirPort Extreme Base Station (802.11ac model) or AirPort Time Capsule.
  • AirPort Time Capsule.
  • A Mac shared as a Time Machine backup destination.
  • Network-attached storage (NAS) device that supports Time Machine over SMB.

How do I set Time Machine up?

When connecting a new disk to your Mac setting up Time Machine should be a simple two step process.

  1. Connect the drive to your Mac and you will be asked if you want to use the drive to back up with Time Machine. 
  2. Then click Use as Backup Disk (For added security select Encrypt Backup Disk).
Adding a backup disk to Time Machine
Adding a backup disk to Time Machine

If Time Machine doesn’t ask to use your drive you can add it manually:

  1. Open Time Machine preferences from the Apple () menu > System Preferences, then click Time Machine.
  2. Click Select Backup Disk (or Select Disk or Add or Remove Backup Disk)
  3. Select your external drive from the list of available disks. 
  4. Then click Use Disk (For added security select Encrypt Backup Disk).

If the disk you selected isn’t formatted in the format required by Time Machine, you will br prompted to erase the disk. Click Erase to proceed. This will erase all information on the backup disk. 

What happens next?

Time Machine will create a full backup of your Mac which may take a few hours. After the initial backup it will backup any incremental changes made to your Mac each hour which should be much quicker.

To ensure the first backup completes successfully we recommend using a network cable if available and not turning off your Mac until it is complete. You will be notified when the backup completes.

Time Machine backup complete notification

To start a backup manually, choose Back Up Now from the Time Machine Time Machine Menu Bar icon menu in the menu bar. Use the same menu to check the status of a backup or skip a backup in progress.

Source: Apple