What you need to know
- macOS Monterey can AirPlay the display of one Mac to another Mac.
- This essentially enables you to use one Mac as an external display.
If you've been wanting to use one Mac as an external display for another Mac, macOS Monterey has your back.
As reported by MacRumors, macOS Monterey will enable users to AirPlay the display from one Mac to an iPhone, iPad, or yes, another Mac. This effectively enables you to use another Mac as an external display for another Mac.
One of the key new features of macOS Monterey is the ability to AirPlay content to a Mac from other Apple devices, such as an iPhone, iPad, or another Mac. According to the macOS Monterey features page, AirPlay to Mac works both wirelessly or wired using a USB cable, with Apple noting that a wired connection is useful when you want to ensure that there's no latency or don't have access to a Wi-Fi connection.
AirPlay to Mac also allows users to extend or mirror an Apple device's display to a Mac, and we've confirmed this works on a Mac-to-Mac basis. This makes it possible for supported Macs to use another Mac as an external display, and with AirPlay to Mac working both wirelessly or with a wired connection, Apple has come close to reviving Target Display Mode, which allowed 2009 to 2014 iMac models to serve as another Mac's external display.
The report does note that unlike Target Display Mode which enabled another Mac to serve as an external display but died long ago, using AirPlay to accomplish this may result in some latency.
It's worth noting that these new AirPlay features do not serve as a complete Target Display Mode replacement, as we've been told that AirPlay compresses video sent from one Mac to another, and at least some latency might still be possible.
macOS Monterey is available in beta for developers now and will release to all users in the fall. If you want another display but don't want to grab another Mac to accomplish that, check out our list of the Best 4K monitors for Mac 2021.