Free tools Windows power users keep installed
One-click scans. No signup required.
To back up a Mac to an external hard drive, connect a compatible drive, add it in Time Machine settings, and let the first backup finish. Apple recommends a backup device with at least twice your Mac’s storage capacity; setup may erase the selected disk, so check its contents before you proceed.
Before you start
- Choose a suitable drive: Apple recommends at least twice the storage capacity of your Mac. For example, for a Mac with 1 TB of storage, Apple says a 2 TB backup disk is ideal. This is guidance, not a guarantee of a particular backup history: how much you can keep also depends on your data and how it changes over time. When the disk fills, Time Machine deletes the oldest backups to make room for new ones. Apple’s Time Machine guidance was published July 6, 2026.
- Check the connection: Connect the drive to a compatible port on your Mac. Apple gives USB-C and Thunderbolt as examples; the right cable or adapter depends on the ports on both devices. Apple’s port and connector guide can help identify the Mac’s ports.
- Protect files already on the drive: Time Machine setup may offer to erase and reformat the disk. Copy anything you want to keep to another location before accepting an erase, or use a different drive or volume.
Set up the external drive in Time Machine
- Connect the external drive to your Mac.
- On macOS Ventura 13 or later, open the Apple menu and choose System Settings > General > Time Machine.
- Click Add Backup Disk or the Add button, select the external drive, then choose Set Up Disk.
- Read any prompt about erasing or reformatting. Apple prefers APFS or APFS Encrypted for Time Machine. Do not continue with an erase unless you have moved any wanted files off the disk.
- If you want an encrypted backup, turn on Encrypt Backup and create a password. Keep it somewhere safe: Apple says you need that password to restore files from the encrypted backup.
- Allow the initial backup to complete. Apple notes that the first backup may take longer, but you can continue using your Mac while it runs.
These menu names and steps apply to macOS Ventura 13 or later. If you use another macOS version, consult the instructions for that version rather than assuming the labels are identical.
What Time Machine backs up and how it runs
After the first backup, Time Machine backs up files that have changed. It runs automatically, and if you disconnect the external drive, its schedule resumes when you reconnect it. Eject the drive or shut down your Mac before unplugging it.
Time Machine can back up personal files and other content, but Apple says it does not back up system files or apps installed as part of macOS installation. Treat it as a way to restore backed-up data, not as a bootable clone or a replacement for every macOS recovery step.
#1 Best Overall
- Easily store and access 2TB to content on the go with the Seagate Portable Drive, a USB external hard drive
- Designed to work with Windows or Mac computers, this external hard drive makes backup a snap just drag and drop
- To get set up, connect the portable hard drive to a computer for automatic recognition no software required
- This USB drive provides plug and play simplicity with the included 18 inch USB 3.0 cable
- The available storage capacity may vary.
On APFS disks, macOS also keeps local snapshots hourly, retaining them for up to 24 hours or until space is needed. These snapshots are stored on the Mac; they are not a substitute for the external backup.
Restore files from the backup
To retrieve selected items, open Time Machine and choose Browse Time Machine Backups, then find and restore the files you need. Apple says a Time Machine backup can restore some or all files to the same Mac or to another Mac. Backups made on macOS 12 or later can be restored only to a Mac running macOS 11 or later.
Rank #2
- Easily store and access 5TB of content on the go with the Seagate portable drive, a USB external hard Drive
- Designed to work with Windows or Mac computers, this external hard drive makes backup a snap just drag and drop
- To get set up, connect the portable hard drive to a computer for automatic recognition software required
- This USB drive provides plug and play simplicity with the included 18 inch USB 3.0 cable
- The available storage capacity may vary.
If an external drive is not the right destination
A directly connected drive is a straightforward choice for this setup. Apple also lists a Mac shared over a network and compatible network-attached storage (NAS) as possible destinations; a NAS must support Time Machine over SMB. Those options have different setup requirements, so confirm compatibility before relying on them. Apple’s list of Time Machine backup disks describes supported destination types.
Quick Recap
Best Value
- [Upgraded Version] - This external hard drive features a mirrored logo stripe combined with a striped anti-slip design, and the rounded corners of the casing make it easier to grip. The stripes also have a heat dissipation function, ensuring stable and fast data transfer.
- 【Ultra-thin and quiet】 - The motherboard adopts JMicron 578 noise-free solution, giving you a quiet working environment. Lightweight and portable size designed to fit in your pocket for easy portability.
- 【Ultra-Fast Data Transfers】 - Pairing this external hard drive with JMicron 578 solution USB 3.0 and USB 2.0 interfaces enables blazing-fast data transfer. It boasts theoretical read speeds of up to 125MB/s and write speeds of up to 103MB/s.
- 【Plug and Play】 - With no software to install, just plug it in and the drive is ready to use.The hard disk chip is wrapped with an aluminum anti-interference layer to increase heat dissipation and protect data.
- 【What You Get】 - 1 x Portable Hard Drive, 1 x USB 3.0 Cable, 1 x User Manual, Gift-type shell packaging ,Three-year manufacturer's warranty and free technical support services.
Rank #4
- Easily store and access 4TB of content on the go with the Seagate Portable Drive, a USB external hard drive.Specific uses: Personal
- Designed to work with Windows or Mac computers, this external hard drive makes backup a snap just drag and drop
- To get set up, connect the portable hard drive to a computer for automatic recognition no software required
- This USB drive provides plug and play simplicity with the included 18 inch USB 3.0 cable
- The available storage capacity may vary.
Rank #3
- Easily store and access 1TB to content on the go with the Seagate Portable Drive, a USB external hard drive.Specific uses: Personal
- Designed to work with Windows or Mac computers, this external hard drive makes backup a snap just drag and drop. Reformatting may be required for Mac
- To get set up, connect the portable hard drive to a computer for automatic recognition no software required
- This USB drive provides plug and play simplicity with the included 18 inch USB 3.0 cable
- The available storage capacity may vary.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
