Second Display

How to use an old iMac as a second monitor for your MacBook, Mac mini or Mac Studio. Second Display is a Mac app that does it over a Thunderbolt cable, with a lossless picture (nothing is compressed), or over Wi-Fi and Ethernet.

Target Display Mode ended with the mid 2014 iMacs. Second Display works on iMacs from late 2015 on, Intel or Apple silicon, with macOS 12.3 or later. The Mac you work on needs macOS 14 or later.

The videos cover setup over a cable or Wi-Fi, picking a quality level, and using the iMac's speakers, microphone and camera from your Mac. Others show several displays at once and fixes for stutter and sleep problems.

Try it free for 7 days, no card needed, then $39, paid once: seconddisplay.app