Using Old iMacs As Display For Laptop

Is it possible to use old iMacs as a primary and/or secondary display for a new MacBook Air M1 laptop?

Our family has the following:

  • a mid 2011 iMac 27" (2.7GHz Intel Core i5) running High Sierra (10.13.6)
  • a late 2015 iMac 27" (3.3 GHz Quad-Core Intel Core i5)

The 2011 is on its last legs so was wondering if it could just be used as a display.

Other option is that when Apple releases a large screen (30"+) iMac M1 (and they will :slight_smile: ), we’ll get rid of the 2011 but keep the 2015 one to use as an extra display or other generic purposes. Would love to know if they can be used as displays. I did some research but it wasn’t fully clear on what my options would be.


Not really.

Apple used to have a feature called “Target Display Mode” which would do this, but it’s no longer supported.

Source: Use your iMac as a display with target display mode - Apple Support

Target display mode requires macOS High Sierra or earlier on the iMac used as the external display. It does not work with macOS Mojave or later.

The only option that I am aware of is Luna Display, but it requires that macOS be running on the iMac, so if the iMac itself dies, it will no longer work.

Yes, I am reading this thread on a mid-2011 iMac 27" running in target display mode. As noted above, it is running on High Sierra. I know iMacs 2015 and later cannot be used in target display mode. Where the cutoff lies between 2011 and 2015, I’m not sure, but given the computers you have (which match mine), it probably doesn’t matter to you. So, your 2011 will work in TDM (so long as you don’t upgrade High Sierra) but the 2015 won’t no matter what OS you use.

Apparently you can if you’re adventurous. You can buy a controller for the lcd panel and make it into a display.

I have a 2019 MBP and use my 2013 21” iMac in TDM. My understanding is once retina came to the iMac the feature went away but as long as you have an iMac that supports it your should be able to use it.

Thanks for all the responses! It appears the consensus is that it may be possible with the 2011 iMac but not so much with the 2015 one.