I have a big new TV and am wondering if I can use it as a second screen for my Mac system? In particular, I’d love to be able to have it duplicate what’s on my computer screen. Running MacOS 11.3.
Windows and Mac systems both for many years have been able to work with a second screen with remarkably little effort. Plug in an HDMI wire and you’re good to go. Heck, with the right television set, you might be able to skip the wire entirely and connect via Chromecast or AirPlay if supported. My Vizio TV supports both protocols so there really are a lot of ways that I can have my Mac push content (often a streaming service or YouTube video) onto my big screen. But at its most basic, all you need is a long HDMI wire (10′ cables are under $10) and any adapters that might be required on your Mac to ensure you can plug it in. My MacBook Pro, for example, only has USB-C ports, so I need to use an HDMI to USB-C adapter (about $20).
A lot of the long HDMI wires have a directionality so you’ll want to look carefully at the plugs to see if either says “source” or “computer” or “source” and hook it up appropriately. Thicker HDMI cables seem to be bidirectional and so sidestep this issue. Then pay attention to what port you plug into on your TV so you can then choose that matching port with the “input” button on your remote. It’ll probably be called something like “HDMI 3” or similar.
CONNECTING A SECOND SCREEN TO YOUR MAC SYSTEM
The basic process is identical whether you’re hooking up a fancy 4K computer monitor or plugging into your TV: Plug in all the cables and adapters, turn on the display, and wait a few seconds. Your Mac screen should go black for a second or two, then come back, but now it’s also pushing a video signal to the second screen.
To configure it, go into Apple > System Preferences… and choose Displays:
If you open it up and only see three tabs along the top, then there’s a problem:
That’s what you’ll see if there’s a problem. Try unplugging and replugging everything in again, make sure your TV is turned on and its input is switched to the HDMI connection.
What you seek is to have four entries along the top tab, as you can see here:
What’s new is “Arrangement” and that’s key to setting things up the way you want. Before we proceed, however, notice the “AirPlay Display” option at the bottom. If your TV supports AirPlay (or you have an AppleTV), that’s where it’ll show up: choose it from the pop-up menu and you’ve got a second screen without any wires involved! Cool!
Note: Chromecast doesn’t show up as an entirely new screen, it lets you send specific content (like a YouTube video or a full tab of Web content from within Google Chrome) to the display, so it’s not exactly analogous on a Mac system.
Let’s check out the “Arrangement” tab because it’s incredibly helpful!
There are two basic ways you can use a second display; to duplicate or mirror your content, or as an extension of your computer Desktop with its own windows, menubar, etc. The default is to have it as an extension. You can see above that the TV shows up “on the right” of my main screen (denoted with the tiny white menubar graphic on its top).
What does “on the right” mean? Literally that it’s as if the Mac screen suddenly stretched on its right; Move the cursor to the very right edge of your screen and it’ll show up on the TV! Click and drag a window or app off your Mac screen to the right and it’ll show up on the TV screen! Pretty amazing the first time you do it.
But the Arrangement feature is even better because you can click and drag the second box to match your physical configuration. If your second screen is physically above your Mac, perhaps wall mounted, you can move it above on the arrangement too. On the left? Doable.
Meanwhile, a whole new settings window has appeared on the second display too. On mine you can see that I am using a Toshiba TV for this demo:
If you aren’t getting a crisp, stable image, you can experiment with the refresh rate or underscan setting, but I’ve found just about 100% of the time that the defaults work great.
But what if you do prefer to have the exact same content on both screens? Then click the “Mirror Displays” checkbox on the lower left of the System Preferences window. The Arrangement changes rather significantly:
And that’s it, everything you need to know so you can get the most out of a second display, whether it’s a fancy 4K monitor or a convenient television screen. Remember also that when you move a window to the second screen, going “full screen” means you’ll lose all your Mac window frame, the menu bar, etc, so Netflix in a browser window, for example, goes edge-to-edge and looks indistinguishable from having native Netflix on the unit. I do this all the time, particularly in hotel rooms where I can watch whatever I want on the room television!
One more thing: if the audio is still coming out of your computer, go to Settings > Sound > Output and choose your HDMI screen (it might show up as your TV’s brand name too). Easy!
Pro Tip: I’ve been writing about the Mac since, well, the very beginning. Please check out my extensive Mac help library for hundreds of useful tutorials and how-to guides. Thanks!