How to Use an iMac as a Monitor With Target Display Mode

Simon Slangen 24-03-2014

More is not always better, but it’s probably true in terms of screen real estate 3 Things You Can Do With Old Computer Monitors Unused electronics are the bane of the modern life. Perfectly functional gadgets sit quietly in a corner of the store room, doing nothing. Old LCD monitors are a perfect example of that. Read More . The iMac scores a lot of points in that area; one of its biggest strengths being the big, vibrant screen it sports. Even if you don’t use the iMac as your main computer (anymore), you can put that screen to work How To Take Advantage Of Your Widescreen Apple Display [Mac OSX] I didn't realize until I unpacked my 27" iMac just how much screen real estate I had to work with. Sure, it looked large in the store, but opening numerous applications and windows on it,... Read More using the iMac’s Target Display Mode.


Target Display Mode

Realising its potential, Apple first introduced Target Display Mode for the 27″ 2009 iMacs running Mac OS X 10.6.1 or later. As the name implies, TDM allows you to use your iMac as an external monitor for your other supported devices. Depending on the make and model of your iMac and source computer, you can even seed audio to the iMac.

Using your iMac’s other facilities, like the webcam and optical drive, is not supported. The emphasis still lies on the iMac’s display.


While in Target Display Mode, you essentially take away the iMac’s screen (and possibly sound) capacities. The iMac doesn’t have to be rebooted, but continues running its own applications in the background, just hidden for the time being. When you go out of Target Display Mode or put your source computer to sleep, the iMac reclaims its screen and heads off from there.

Compatibility (Video)

The idea is to connect the Mini DisplayPorts or Thunderbolt ports of your iMac and your source computer. Because of the differences between Thunderbolt and Mini DisplayPort Why Apple's New Thunderbolt Port Is Awesome [Technology Explained] I/O ports aren’t a technology that folks spend a lot of time thinking about. Let’s face it – they’re not sexy. Still, ports are important. As the interface between your computer and everything else, your... Read More , compatibility between devices depends on the ports that are available and the cable you use to connect them.



It boils down to this: If you have an old iMac with a DisplayPort, you can use a source device that has either a DisplayPort or a Thunderbolt port as long as you use a DisplayPort cable. However, later iMacs with a Thunderbolt port must be connected with a Thunderbolt source device using a Thunderbolt cable. If that makes your head spin, just look up your iMac in the table below to see what cables and source devices are supported. In all cases, your iMac is expected to be running Mac OS X 10.6.1 or later.


To find out which model you have standing on your desk, click the Apple logo in the top left-corner of your screen, choose About This Mac… then More Info… You’ll can find the model number at the top of the info panel. To find out if your computer has a Mini DisplayPort or Thunderbolt port, go to this same screen and press System Report… If you have a Thunderbolt-equipped computer, it should be listed under Hardware.



Alternatively, look at the icon next to the physical port on your computer. Thunderbolt is marked with a lightning bolt icon, Mini DisplayPort looks similar, but is marked with a square-shaped icon.

Compatibility (Audio)

The above specifications need to be met to be able to use Target Display Mode and start using your iMac as an external display. Depending on your source device, you might also be able to use the iMac as an audio output device when in Target Display Mode.



If your source device has a Thunderbolt port, audio transmission is supported by default. Some Mini DisplayPort Macs can also output audio. To check, go to Apple > About This Mac… > System Report… and select Audio from the Hardware list in the side bar. If HDMI Output or HDMI/DisplayPort is listed, audio output is supported on that computer. On top of that, you’ll need to make sure you’re using a Mini DisplayPort cable that also supports audio transmission.

What About Connecting Non-Mac Devices?

When presented with a big iMac display, a lot of people would rather connect their Xbox or PlayStation than their MacBook. If you’re wondering if it’s possible to connect a non-Mac device to your iMac, the answer is yes and no.

If you have an older iMac with Mini DisplayPort (27-inch Late 2009, or 27?inch Mid 2010), the answer is yes. Apart from another device equipped with Mini DisplayPort, you can use a third-party adapter to convert HDMI to Mini DisplayPort, like the Kanex XD.



Alas, if you have a newer iMac with Thunderbolt support you need to use a Thunderbolt source, so you won’t be able to use adapters like those mentioned above. Bad luck.

 How To Enable Target Display Mode

If you’ve checked the above list for compatibility, and you have a supported cable and source device, going into Target Display Mode is very easy. Just connect the Mini DisplayPort/Thunderbolt ports of both devices with the cable and press cmd+F2 on the iMac. (Apple recommends using the official aluminum Apple keyboard on your iMac, because it can’t guarantee support for other keyboard models.)

You can use your iMac’s speakers (if compatible, see above) like you would any other external speakers. Just go to System Preferences -> Sound -> Output to choose your audio output device.


Once you’re in Target Display Mode, you can use the media and brightness keys to control your iMac’s display and media playback, but the other keys on the keyboard will be disabled. To exit Target Display Mode, just hit cmd+F2 again or disconnect the source computer.

Will you be using your iMac as an external display? Maybe even repurpose a sluggish 2009 iMac as a monitor? Let us know in the comments below the article!

Related topics: Computer Monitor, Thunderbolt.

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  1. Arek
    August 21, 2019 at 9:57 am

    Can i use a Mini DisplayPort to DisplayPort adapter to connect a PC to a 2009 iMac?

  2. Stephan
    July 17, 2018 at 8:47 am

    The article mentions it will work with non Mac devices "If you have an older iMac with Mini DisplayPort (27-inch Late 2009, or 27?inch Mid 2010), the answer is yes"
    Does this apply to the mid 2010 21.5" iMac?
    I want to use a Windows laptop (acer swift, running win 10) and project it to my old iMac mentioned above. I read a lot contradictory info online and it's difficult to make an informed decision about which adapter to buy or if I should get an adapter at all.
    Thanks for your help (if you are still monitoring this thread)

    • Douglas Novo
      July 28, 2018 at 3:58 pm

      No. For the 2009 and 2010 iMacs only the 27" models supported Video target mode.

  3. jussi
    May 5, 2018 at 11:30 am

    I can confirm this! I have a late 2009 27" iMac. Just hooked up a 2018 Dell Latitude PC laptop using a mini display port cable. Works great as an external monitor!

  4. Karl
    July 3, 2017 at 9:15 pm

    All of these instructions are correct! If anything, be sure to use a BELKIN BRAND MINI DP cable when executing this. I had tried a no name brand cable and it did not work!

  5. Andrea
    June 16, 2016 at 6:59 pm

    Same problem as daniel "I have a 2009, 27 inch Imac. I bought a Mini Display port to HDMI Adapter, then i put it into my Imac, then i put the PS3s HDMI into the adapter, and i keep pressing cmd + F2 and nothing is happening, i enabled the keys to do normal things and it still does not work. Is there anything i missed out?I have a 2009, 27 inch Imac. I bought a Mini Display port to HDMI Adapter, then i put it into my Imac, then i put the PS3s HDMI into the adapter, and i keep pressing cmd + F2 and nothing is happening, i enabled the keys to do normal things and it still does not work. Is there anything i missed out?"

    • joevt
      June 29, 2018 at 6:22 pm

      You need a HDMI 1.4 to DisplayPort adapter (should allow 2560 x 1440 at 60 Hz). These adapters usually use a USB connection for extra power.

      I think the Kanex XD linked in the article only supports HDMI 1.0 (1920 x 1200 at 60 Hz).

      There also exists much more expensive HDMI 2.0 (3840 x 2160 at 60 Hz) to DisplayPort adapters that use an external power brick. These should also work to allow 2560 x 1440 at 60 Hz.

  6. sophie
    June 14, 2016 at 8:00 pm

    Would this work on a TB port on an MBA 2015 with 10.11 running?

    • joevt
      June 29, 2018 at 6:25 pm

      Yes, if you mean you want to use an iMac as a display for the MBA 2015. The MacBook Air has a Thunderbolt port so it should work with any of the iMacs that support Target Display Mode.

  7. Daniel Deguara
    December 24, 2015 at 12:24 pm

    I have a 2009, 27 inch Imac. I bought a Mini Display port to HDMI Adapter, then i put it into my Imac, then i put the PS3s HDMI into the adapter, and i keep pressing cmd + F2 and nothing is happening, i enabled the keys to do normal things and it still does not work. Is there anything i missed out?

    • joevt
      June 29, 2018 at 6:27 pm

      Wrong adapter. See my reply above to Andrea.

    • joevt
      June 29, 2018 at 6:32 pm

      The 5K iMacs are not on the list of iMacs that support Target Display Mode. Read Apple Support document ht204592 "Use your iMac as a display with Target Display Mode".

  8. cris
    April 26, 2015 at 2:02 am

    HI ,I'm thinking in buying a retina 5k imac ,i was just wondering if i can connect my xbox one to it ???? thanks in advance

    • joevt
      June 29, 2018 at 6:33 pm

      No 5K iMac support Target Display Mode. Read my reply above to Nick.

  9. Robin
    March 29, 2015 at 1:57 pm

    Hi, I have a 27" mid-2011 model iMac, and I was hoping to find out if using a Thunderbolt to HDMI adapter cable would allow me to use my Mac as a display for my PS3 / PS4, before I would purchase such an adapter. If this is not possible by default, I would like to know... Is this because of HDCP, or does TDM just not work for HDMI devices regardless of HDCP?
    I have a way to get around the HDCP (I use it for gameplay recording), so if that is the only thing standing in the way, I might buy one of those adapters. Thanks in advance!

  10. tope
    March 4, 2015 at 8:55 am

    HI, please how can i repair my mac system which screen is just blank and keyboard and mouse not working
    i also have another mac system that just restart itself

  11. Eli
    February 21, 2015 at 3:17 am

    Silly question I know, but could you use an iMac with a faulty logic board as a screen only?

  12. Hadlee
    February 12, 2015 at 3:04 am

    Hello I was wondering if there is a way to set you imac to start up as a external monitor by default

    • Marius
      January 18, 2019 at 2:42 pm

      there is a program called virtualKVM, it will wake up your imac as an external screen. but it will not put it back into sleep mode like normally.

  13. Martin
    February 10, 2015 at 11:05 am

    I have a mid 2010 Imac 27" (with mavericks 10.9.5) and a MBP mid 2012 (with Yosemite 10.10.2). Now where can I purchase a working mini diplayport to mini diplayport cable? Because only has thunderbolt. And no web shops in Norway have mini diplayport to mini diplayport cables. And the china-copy I got from "" (after waiting three weeks) does not work. Would hdmi with adapter do the trick?

  14. Scott
    January 7, 2015 at 11:57 pm

    seems an awful lot of 2010 iMacs are failing now. i just had to purchase a new iMac because of the same issue and was wondering the same thing. hmm...

    • Marius Ihlar
      September 6, 2019 at 9:02 am

      Still rockin my 2010 iMac. haha!
      It's a bit slow, but still runnin.

  15. Jesse Matthews
    January 6, 2015 at 4:10 am

    My late 2010 iMacs's HDD crapped out and won't boot to the OS (it just loops). Is there a way to just boot into TDM without having to boot to the dashboard? I just can't justify tossing such a beautiful display if there is a chance to use it without repairing the HDD.

    • Mark
      September 12, 2016 at 10:05 pm

      Was this ever answered? I would love to do the same with my old iMac (same problem as yours) but looking to see if it is possible

    • Paulo Cholla
      January 23, 2017 at 9:22 pm

      try booting then press and hold T

  16. Cosmo
    July 23, 2014 at 11:56 pm

    I have a late 2009 27" iMac whith a year old replaced screen and would like to use it as an additional monitor with my new iMac. Unfortunately the graphics card went haywire and I don't want to spend all the money Apple is asking to repair. It still works in "safe mode" and also works in standard startup after I disabled the grpahics card startup items (basically functioning like safe mode) I have no issues with crashing now. It it is obviously not a full functioning computer but the screen and operating system are still go. I decided to purchase a new iMac and was wondering if anyone knows if TDM will work with the old iMac in this condition. Also, when using TDM, are both screens functioning? The whole point would be to increase the screen real estate of the new iMac - not just use the larger 27". Thanks.

  17. Thomas Keppel
    April 24, 2014 at 12:42 pm

    I am trying to connect my HDSLR camera (HDMI port) to my late 2012 iMac via the Thunderbolt port - without luck so far. Any suggestions?

  18. Damian D.
    March 27, 2014 at 4:10 pm

    Thank you for this amazing tip. I recently purchased a new iMac and was wondering how to repurpose my older, early 2008 24" iMac. I didn't want to throw it out because it is still good, I just can't use it for video editing anymore. Right now I have them sitting side by side, and I'm glad I can repurpose it as an external monitor for my current setup. Thanks for this tip.

    • Simon S
      March 28, 2014 at 1:56 pm

      It'd be a shame to throw it out, especially with a screen like that. Good luck!

    • Damian D.
      March 31, 2014 at 4:53 am

      I agree, it would be a shame to have to get rid of it specially when I read so much about other uses that an older mac can service.
      So now, I have to connect my old iMac via the display port to my new iMac via thunderbolt conection? so I will need to get the wire as well as a display adapter from thunderbolt to Display adapter…. right?

    • Simon S
      March 31, 2014 at 7:56 am

      @Damian D.

      I'm sorry, I only just noticed the iMac model you mentioned in your original post. As mentioned in the article, TDM was only introduced in 2009 and later iMacs, so it won't be available for yours.

      Alternatively, you could use an application like Air Display to use your iMac as an external display. It's what I used before I found out about TDM.

      Best of luck.

  19. Yannis V
    March 25, 2014 at 12:50 pm

    I didn't know about TDM. This makes adding a Mac Pro to my setup a whole lot easier.