How to use Target Disk Mode on Intel and M-chip Macs

Ever been in a situation where your Mac is acting up? Or maybe your internal drive seems to be failing, and you must rescue everything? I've been there, and I can say that Target Disk Mode (TDM) is a lifesaver.

I've used the Target Disk Mode Mac tool countless times for all these, and today, I'll walk you through setting it up and using it. I'll even throw in a few pro tips to make your data management smoother.

What is Target Disk Mode?

Target Disk Mode (TDM) is a special boot mode that allows a Mac computer to be used as an external drive by another Mac. When you set one Mac to TDM and connect it to another, it will appear in the Finder window. You can then transfer data, format, or partition it as you would an external drive. If the two Macs meet certain conditions (we'll look at them later), you can use an operating system from the target Mac to boot the host.

It’s important to note the setup requirements for TDM on different Macs:

• Silicon-based Macs (M1 to M4): The feature is called Share Disk or Mac Sharing Mode, with a different setup process.
• macOS 11 Big Sur or later: Target Disk Mode (TDM) requires a Thunderbolt cable to work.
• Older macOS versions and Macs: TDM can be used with Thunderbolt, USB, or FireWire cables.

Check out the detailed article on the complete list of all macOS versions.

How to enter Target Disk Mode

Entering Target Disk Mode is simple but varies by Mac type. For Intel Macs, hold the T key during startup. For Apple Silicon Macs, press and hold the power button until the options appear, then choose Target Disk Mode. This lets one Mac function as an external drive for easy file transfers. Let’s get into the details below.

Using Target Disk Mode on Intel-based Macs

Here's the step-by-step process for the Intel version:

1. Connect the two Macs using a USB, USB-C, or Thunderbolt cable.
2. Enter Target Disk Mode on the Mac you want to use as an external drive:

• If the Mac is off: Press the power button and hold the T key.
• If the Mac is on: Go to the Apple menu bar > System Settings > General > Startup Disk > Click Restart and choose Target Disk Mode from the options.

3. Open a Finder window on the host Mac.

4. The Mac in Target Disk Mode will appear as an external disk in the sidebar. Simply double-click it to access its files.

You can now transfer files by dragging them to and from the target storage. Once you are done, press the power button to shut down the Mac and disconnect the cable.

If your Mac can’t see an external drive, check out how to access an external drive that's not recognized on a Mac.

Using Target Disk Mode on Silicon-based Macs (M1/M2/M3/M4)

The way things work for the M series is a little different. Here’s a straightforward step-by-step breakdown for the Silicon version:

1. Connect the two computers using a USB, USB-C, or Thunderbolt cable. 
2. Shut down the target computer at the Apple menu bar > Shut Down.
3. Press and hold the power button until Loading startup options appears on the screen.
4. Click Options > Continue.
5. Select a startup disk > Next. Your Mac will start in macOS Recovery mode. You may need to enter your password to continue.
6. Choose Utilities and click Share Disk.
7. After selecting the disk or volume, click Start Sharing.
8. Open Finder on the other Mac > click Network under Locations.
9. Double-click the Mac that has the shared disk or volume.

Learn more about the difference between M1 and M2 chips and M3 and M4 chips.

Transfer data using Target Disk Mode

Transferring data between two Macs is quick and easy. You can either migrate files to a new machine or recover data from a Mac that won’t start.

Here’s what to do: 

1. Prepare both Macs: The most important part of transferring data via TDM is using the right cable (same ports). However, you can still use an adapter for incompatible versions, such as Thunderbolt 2 and 3. 
2. Enter TDM: Now, connect the two computers using Target Disk Mode.
3. Access the drive: On the host Mac, open a Finder window. On Intel-based Macs, the shared computer should appear like an external disk (Macintosh HD) on the left panel. If you are using a Silicon one, open a Finder window, then go to Network and double-click on the shared Mac. 
4. Move files: You can drag and drop any file or folder you want to and from the target storage shared Mac.
5. Eject safely: Right-click the drive in Finder, then select Eject to disconnect the drive safely.
6. Once you are done, power off the source Mac before unplugging the cable.

This method of transfer is quite fast for both small and large files. When transferring a 12GB file, I got speeds averaging 2 GB/s. However, from experience, Target Disk Mode Mac speeds can be quite irregular and vary depending on the cables you are using and the type of data you are copying.

As an alternative, I recommend DComannder. It's a versatile file manager with a dual-pane view that makes copying and transferring data relatively easy. You can use the app over a network to move large files or just a few small ones with ease. The app will speed up the data transfer process and give you more control with customizable views.

How to boot using Target Disk Mode

Target Disk Mode isn't all about moving files around — it also allows users to repair a drive and even boot up another Mac. The latter comes in handy when your OS misbehaves, or your Mac has a problem with its internal drive. Once you boot it up with another Mac, you can reinstall the OS or run the repairs your Mac desperately needs. However, before you proceed, note that booting the OS using TDM has a few requirements:

• The two Macs should be identical (year and model)
• The OS version should be the same (one more reason you should always run the latest version).

If your two computers meet these conditions, you are all set. Now you need to:

1. Shut down the source Mac (the one you want to boot from) and the target Mac.
2. Connect the two using a Thunderbolt, USB-C, or FireWire cable.
3. Enter Target Disk Mode on the source Mac.
4. Push the power button on the target Mac while holding the Option key.
5. Choose the source Mac's drive from the list of options (probably labeled as Macintosh HD)
6. Choose it and press Return to boot from the drive.

You can now sort out the issues preventing you from booting up your Mac.

Alternatives to Target Disk Mode

Target Disk Mode on a Mac is pretty powerful, but it’s not the only way to transfer files, and it might not even be the most straightforward option out there. There are other methods that could make moving your files a lot simpler.

File Sharing: Apple’s built-in tool

Apple's File Sharing is enough if you only need to move a few files here and there. It can also copy and move files to another Mac, and it's even much more straightforward as you only need to share them via the connected network. 

Here's how it works:

1. On the Mac you want to share files from, go to the Apple menu bar > System Settings > General > Sharing.
2. Turn on File Sharing.
3. On the other Mac, open Finder and navigate to Network.
4. You'll see the shared Mac appear in the list. Simply drag and drop any files you need between the Macs.

Note that both computers need to be on the same network, and the method may be slow for larger files.

Dropshare: Cloud file sharing

Instead of moving your data every now and then, you can simply upload it to the cloud. However, if you are like me, you use several cloud services for different data types, and switching between them can be pretty annoying.

To navigate this complexity, I find Dropshare super-useful. It's a file-sharing app that works with all major cloud services to give users a seamless way to manage everything in one place. Adding files is quite simple, as you only need to drag and drop them in the menu bar. 

Plus, you can create an access-restricted URL to share your files with a password — a handy method for sensitive documents.

CloudMounter: Quick access to all cloud storage

Downloading cloud data can be quite hectic as you need to move from one website or app to another. However, you can make everything super-easy with CloudMounter, one of my favorite utility apps.

As I deal with multiple cloud services, CloudMounter makes navigation by mounting directly to my Mac's Finder. This means that they all look and feel like part of my local storage, and I can access any file on the cloud like I would on a regular disk.

Harnessing the power of Target Disk Mode

Target Disk Mode continues to be one of the most useful, less-known macOS features. You can use it to transfer data or troubleshoot both Intel-based and Silicon-based Macs. To enhance the process, you can first clean up your drive using CleanMyMac, the most powerful declutter tool for Apple devices.

You can then use DCommander or Path Finder to copy and move your files in a much more robust manner than Finder. If you are also juggling between cloud providers, CloudMounter will help make them appear like a part of your local storage, while Dropshare will ensure 1-click drops to the cloud. All these apps are available on Setapp, and you can try them free for 7 days.