Chromebooks include ports that allow you to connect them to a computer monitor, television, or other display. You can mirror your desktop across multiple displays, or use the additional displays as separate desktops to gain additional screen space.
You can also wirelessly mirror your Chromebook’s entire screen–or just one browser tab–to an external display. That external display just needs a Chromecast or another device that supports Google Cast.
Use a Physical Cable
To physically connect your Chromebook to an external display, you’ll need to use whatever port comes included in your Chromebook. Depending on your Chromebook, you may have one or more of the following ports:
- A full-size HDMI port that allow you to connect a standard HDMI cable to your Chromebook.
- A smaller micro HDMI port that allows you to connect a micro-HDMI-to-HDMI cable to your Chromebook.
- A mini DisplayPort port that allows you to connect a mini-DisplayPort-to-HDMI cable to your Chromebook.
- A VGA port that allows you to connect a VGA cable directly to your Chromebook. VGA is old and you should avoid using it if possible, but some older projectors may still require VGA connections.
Depending on the device you’re connecting your Chromebook to, you may need one of several adapters. For example, if your Chromebook has a micro HDMI port and you want to connect it to an older projector that requires a VGA connection, you’ll need to get a micro-HDMI-to-VGA adapter cable.
If you’re not sure which port your Chromebook has, consult the manual or specifications for your specific model of Chromebook.
Once you have the correct cable, simply use it to connect your Chromebook to your external display.
Adjust External Display Settings
Once you’ve connected, you’ll be able to adjust the external display settings directly on your Chromebook. On your Chromebook, click the status area at the bottom-right corner of the screen and select the connected external screen.
You can choose either “Mirrored” or “Extended Desktop” mode for your displays. In Mirrored mode, you have a single desktop and it’s mirrored on all your displays. In Extended Desktop mode, each display simply gives you more desktop room and they’re separate.
You can also toggle between Mirrored and Extended Desktop modes from anywhere in Chrome OS via a keyboard shortcut. Just press the Ctrl and 
(F4) keys at the same time.
If you selected Extended Desktop mode, you can drag and drop the displays to control how they’re oriented. For example, if the external display is positioned physically above the Chromebook, drag and drop its icon to appear above the Chromebook’s display. You can choose which display you want to be your primary display.
You can also choose the ideal resolution for your external displays if it wasn’t automatically detected properly, and choose a different orientation (rotation) if you want the flip or rotate the image.
The “TV Alignment” feature allows you to adjust the exact position of the picture on the external display, which will be necessary to prevent the picture from being cut off or a black frame appearing around the picture on some TVs. If there’s a problem you can use the arrow keys along with the Shift key to adjust the image so it looks correct on your TV.
Connect Wirelessly with a Chromecast (or Google Cast)
Chromebooks don’t support the Miracast standard for wireless external displays, so the only way to truly establish a wireless connection is with the Google Cast protocol. If you have a Chromecast device connected to the display or another device supports the Google Cast protocol (like a Roku or some Smart TVs), you can use Chromecast to wirelessly “cast” a browser tab or your entire desktop to a display.
If you’re looking at a web page, your actions will be mirrored on the display. You don’t even need the Google Cast extension to do this anymore. Just click the menu button and select “Cast”. You can choose whether you want to cast a single browser tab or your entire desktop from the dialog that appears.
