The short answer
Connect an external drive, then open Apple menu › System Settings › General › Time Machine and click Add Backup Disk (or the + button). Choose the drive and click Set Up Disk. Time Machine then backs up automatically every hour while the drive is connected.
Time Machine is the backup tool built into every Mac. Once it’s set up, it quietly saves hourly backups to an external drive, so you can get back a deleted file or your entire Mac.
What you need
- An external storage device, such as a USB or Thunderbolt drive. Some network storage devices also work.
- Ideally, a drive with at least twice your Mac’s storage capacity.
Set up Time Machine
- Connect the external drive to your Mac.
- Choose Apple menu › System Settings.
- Click General in the sidebar, then Time Machine.
- Click Add Backup Disk (or the + button).
- Select your drive and click Set Up Disk.
- Choose whether to encrypt the backup (recommended for laptops) and set a password you’ll remember.
If your Mac asks to erase the drive, make sure there’s nothing on it you need.
How Time Machine backs up
While the drive is connected, Time Machine automatically makes:
- hourly backups for the past 24 hours,
- daily backups for the past month,
- weekly backups for all previous months.
The oldest backups are deleted when the drive fills up.
To back up right away, click the Time Machine icon in the menu bar and choose Back Up Now.
Check that it’s working
In System Settings › General › Time Machine, you’ll see the date of the latest backup and the next scheduled one. For laptops, plug in the backup drive regularly; backups only happen while it’s connected.
Restore a file
- Open the folder where the file was.
- Click the Time Machine icon in the menu bar and choose Browse Time Machine Backups.
- Use the timeline on the edge of the screen to go back to when the file existed.
- Select it and click Restore.
Restore your whole Mac
When setting up a new Mac or after erasing yours, use Migration Assistant and choose to transfer from a Time Machine backup.
Related guides
On a Windows PC instead? See how to back up a Windows PC. If your Mac stops responding before a backup, here’s how to force quit an app on a Mac.
The bottom line
Plug in a drive, add it in System Settings › General › Time Machine, and let it run. Check the “latest backup” date now and then, and you’ll always have a way back.
Frequently asked questions
How big should my backup drive be?
Ideally at least twice the size of your Mac's storage, so Time Machine can keep older versions of your files for longer.
Will Time Machine erase my drive?
If the drive isn't already formatted for Time Machine, your Mac may need to erase it. Copy anything you want to keep off the drive first.
Is iCloud a replacement for Time Machine?
Not entirely. iCloud Drive and iCloud Photos sync files, but Time Machine keeps a full, versioned backup of your Mac, including apps and settings, that you can restore after a failure.
Why you can trust this guide
- Based on official sources. The steps here are checked against the 2 official sources listed below, such as the help pages of the companies involved.
- Checked and dated. Last checked on November 10, 2026. We update guides when software or advice changes.
- Independent. No company paid for or reviewed this guide. We don't sell products, and ads never influence our advice.
- Open to corrections. Spotted an error? Tell us and we'll fix it. Read how we research.
Sources
- Apple Support — Back up your Mac with Time Machine
- Apple Support — What's the difference between device storage and iCloud storage?
This guide is general information. Menus and features can change with software updates, and steps may differ on your device or version. Back up important data before making big changes. Read our disclaimer.
