The Basic Steps to Cast Your Screen

To cast from your computer to your TV, you need three things: a Chromecast device plugged into your TV, your computer and TV on the same WiFi network, and the Google Chrome browser on your computer. Once those are in place, open Chrome, click the three-dot menu in the top right corner, select "Cast", choose your TV from the list, and your screen will appear on the television within a few seconds.

The process works the same way whether you're using Windows or Mac. Your entire screen will mirror to the TV by default, though you can also cast just a single browser tab if you prefer — this uses less bandwidth and keeps your other open tabs private on your computer.

Key Takeaways

  • You must have Chrome browser installed on your computer and a Chromecast device connected to your TV and the same WiFi network.
  • Click the three-dot menu in Chrome, select "Cast", and choose your TV from the device list to begin mirroring.
  • Casting your entire screen shows everything on your computer, while casting a single tab keeps other windows hidden from the TV.
  • If your TV doesn't appear in the Cast list, restart your Chromecast device and make sure both devices are on the same WiFi network.
  • Audio plays through your TV speakers by default, and you can stop casting by clicking the Cast icon again and selecting "Stop casting".

Setting Up Your Chromecast Device

Before you can cast, your Chromecast must be plugged into an HDMI port on your TV and powered on. If this is your first time using the device, follow the setup instructions that came with it — you'll need to connect it to your WiFi network using the Google Home app on a phone or tablet. Once setup is complete, your Chromecast will stay connected to that network.

Make sure your computer is connected to the exact same WiFi network as your Chromecast. If your home has a 2.4 GHz and 5 GHz network with the same name, try connecting your computer to the 2.4 GHz version — some Chromecast devices work more reliably on that band. You can check which network your computer is on in your WiFi settings.

Casting Your Entire Screen vs. a Single Tab

When you click "Cast" in Chrome and select your TV, you have two options: "Cast your entire screen" or "Cast tab". Casting your entire screen mirrors everything — your desktop, all open windows, notifications, and cursor movements. This is useful for presentations, watching videos, or showing photos, but it means your TV displays whatever you're doing on your computer.

Casting a single tab sends only that one browser window to your TV while keeping everything else on your computer private. This is the better choice if you want to watch a video or view a website on the big screen but need to check email or work on other things without showing them on the TV. To switch between the two, click the Cast icon again and select the option you want.

Troubleshooting When Your TV Doesn't Appear

If your TV isn't showing up in the Cast list, the most common cause is that your computer and Chromecast are on different WiFi networks. Check your computer's WiFi settings and make sure it's connected to the same network name as your Chromecast. If you're unsure which network your Chromecast is on, unplug it for 10 seconds, plug it back in, and watch for the setup screen on your TV — this will show you the network it's trying to connect to.

If both devices are on the same network and your TV still doesn't appear, restart your Chromecast by unplugging it for 30 seconds and plugging it back in. Then restart Chrome on your computer and try the Cast menu again. If the problem continues, restart your WiFi router — unplug it for 30 seconds, plug it back in, and wait for all lights to stabilize before trying to cast again.

Adjusting Audio and Display Settings While Casting

When you cast to your TV, audio plays through your TV's speakers by default. If you want to hear sound through your computer speakers instead, right-click the volume icon in your system tray (Windows) or click the volume icon in the menu bar (Mac), and select your computer's speakers. This is useful if you're casting a presentation and want to speak to the room without the audio also coming from the TV.

You can adjust the brightness, volume, and other display settings on your TV using your TV remote while casting — casting doesn't lock those controls. If the image on your TV looks stretched or cut off, check your TV's picture settings or input settings to make sure it's set to display the full image without overscan.

Stopping the Cast and Disconnecting

To stop casting, click the Cast icon in Chrome (it will be highlighted in blue while casting is active), and select "Stop casting". Your screen will when ready return to showing only on your computer, and your TV will go back to whatever it was displaying before you started casting. You don't need to do anything on your TV or Chromecast — the connection stops from your computer.

If you want to cast again later, your Chromecast will still be on the same WiFi network and will appear in the Cast list when ready. You don't need to set it up again unless you change your WiFi password or move the device to a different network.

Common Mistakes to Avoid

The most frequent problem is forgetting to check that both devices are on the same WiFi network. Before troubleshooting anything else, verify this in your settings. Another common mistake is trying to cast before Chrome has fully loaded — wait a few seconds after opening Chrome before clicking the Cast menu, especially on older computers.

Don't assume your TV is off if it doesn't appear in the Cast list. Some TVs need to be powered on and set to the correct HDMI input before Chromecast will show up. If you've just plugged in your Chromecast for the first time, give it a full minute to boot up before trying to cast. Finally, if you're casting a video and it keeps stopping or stuttering, move your computer closer to your WiFi router or Chromecast device — thick walls or distance can weaken the connection.

Frequently Asked Questions

Can I cast from my laptop while it's plugged into a projector?

Yes. Your laptop can send video to both your projector and your Chromecast at the same time. The projector stays connected through its cable, and the Chromecast receives a separate wireless signal. Both will show the same image if you're casting your entire screen, or you can cast a different tab to your TV while the projector shows something else.

What if my computer is on WiFi but my Chromecast is connected with an ethernet cable?

That's fine. As long as both devices are on the same network — whether one uses WiFi and the other uses ethernet — they can communicate. The Cast menu will still find your Chromecast and casting will work normally.

Does casting use a lot of internet bandwidth?

Casting uses your local WiFi network, not your internet connection, so it doesn't count against your data plan. However, if you're casting a video from a streaming service like YouTube or Netflix, that video still needs to read from the internet. The casting itself is just the signal telling your TV what to display.

Can I cast if my computer is on a guest WiFi network?

No. Your computer and Chromecast must be on the same WiFi network to communicate. If your Chromecast is on your main network and your computer is on a guest network, they won't see each other. Connect your computer to the same network as your Chromecast.

What happens if I close my laptop while casting?

Closing your laptop will stop the cast when ready. Your TV will return to whatever it was showing before you started casting. If you need to step away while casting, put your laptop to sleep instead of closing it — the cast will continue as long as your computer stays connected to WiFi.