What casting your monitor means and when you'd do it

Casting your monitor to your TV means sending the display from your computer—everything you see on your screen—wirelessly to a television. Your TV becomes a second display, showing exactly what your monitor shows, or you can extend your desktop so different windows appear on each screen.

People do this to watch videos on a bigger screen, present slides to a room, play games on the TV, or straightforward get more workspace by using the TV as an extra monitor. The setup depends on what device you're casting from (Windows PC, Mac, or Chromebook) and what's plugged into your TV.

If you already have a Chromecast device plugged into your TV's HDMI port, you're partway there—but the steps differ depending on your computer's operating system. This guide covers the most common routes.

Key Takeaways

  • Casting from a Windows PC to Chromecast uses the built-in "Cast" feature in Windows 10 and 11, found in Settings or the Quick Settings menu.
  • Mac computers cannot cast directly to Chromecast; you'll need third-party software like Google Home app or a wired HDMI connection instead.
  • Your computer and Chromecast must be on the same Wi-Fi network for wireless casting to work.
  • Casting mirrors your entire screen by default, but Windows lets you extend to use the TV as a separate display.
  • If casting fails, restart both your computer and Chromecast device, then check that Wi-Fi is working on both.

Casting from Windows 10 or 11 to Chromecast

Windows 10 and 11 have a built-in casting feature that works with Chromecast. Open the Quick Settings menu by pressing Windows key + A, then look for the "Cast" tile. Click it, and Windows will search for nearby Chromecast devices on your network.

When your Chromecast appears in the list, click its name. A second window will ask whether you want to mirror your entire screen or extend your display. Choose "Mirror" to show the same thing on both screens, or "Extend" to use your TV as a separate workspace where you can drag windows between monitors.

If the Quick Settings menu doesn't show a Cast option, you can also reach casting through Settings. Go to Settings > System > Display > Multiple displays, then scroll down and select "Connect to a wireless display." This opens the same casting interface.

Once you've selected your Chromecast, Windows will connect. The first time you cast to a new device, it may take 10 to 15 seconds. After that, reconnecting is usually faster.

Casting from a Mac requires workarounds

Apple's macOS does not include native support for casting to Chromecast devices. If you own a Mac, you have two practical options: use the Google Home app, or connect your Mac to the TV with an HDMI cable.

The Google Home app (available free from the Mac App Store) lets you cast your screen to Chromecast, though the process is less direct than on Windows. Open Google Home, tap the device menu, select your Chromecast, then choose "Cast my screen." Your Mac will ask for permission to record your screen—grant it, and casting will begin.

If wireless casting feels unreliable or you want a permanent setup, an HDMI cable is the simpler route. Connect your Mac to the TV's HDMI port using a USB-C to HDMI adapter (if your Mac has USB-C ports) or a Thunderbolt to HDMI adapter (for older Macs with Thunderbolt). Your Mac will automatically detect the TV and let you mirror or extend the display through System Preferences > Displays.

Making sure your network is ready

Casting relies on your computer and Chromecast being connected to the same Wi-Fi network. Before you start, check that both devices are on the same network—not on different bands (2.4 GHz vs. 5 GHz) if your router broadcasts both.

If your Chromecast isn't showing up in the casting menu, restart it by unplugging the device for 10 seconds, then plugging it back in. While it restarts, also restart your computer's Wi-Fi by toggling airplane mode on and off, or by disconnecting and reconnecting to your network manually.

If you're still not seeing your Chromecast, open the Google Home app on your phone to confirm the device is online and working. If it shows as offline there too, your Chromecast may have lost its network connection—use the Google Home app to reconnect it to Wi-Fi.

Troubleshooting when casting won't start

The most common reason casting fails is that your computer and Chromecast aren't on the same network. Double-check the Wi-Fi network name on both devices. If your router broadcasts a 2.4 GHz and 5 GHz band with the same name, your computer might be on one and your Chromecast on the other—manually switch your computer to match.

If both devices are on the same network but casting still won't begin, restart your Chromecast by unplugging it for 10 seconds. Then restart your computer entirely—not just the Wi-Fi. Close any VPN software you're running, as some VPNs block local network communication.

If you see your Chromecast in the casting menu but the connection drops after a few seconds, move your computer closer to the router or Chromecast. Walls, microwaves, and cordless phones can interfere with Wi-Fi. You can also try switching your router to the 5 GHz band if your Chromecast supports it—5 GHz is often more stable over short distances.

Choosing between mirror and extend mode

Mirror mode shows your entire monitor on the TV. Everything you see on your computer appears on the television at the same time. This is useful for presentations, watching videos together, or gaming on a bigger screen. Your mouse and keyboard still control the computer; the TV is just a display.

Extend mode treats your TV as a second monitor. Your desktop stretches across both screens, and you can drag windows from one to the other. This gives you more workspace—you might open email on your monitor and a spreadsheet on the TV, for example. Extend mode is available on Windows but not on Mac when casting to Chromecast.

To switch between modes on Windows, open the Quick Settings menu again and click the Cast tile. A menu will appear asking whether you want to mirror or extend. You can also reach this through Settings > System > Display > Multiple displays and choose "Extend" or "Duplicate" from the dropdown.

When to use a wired connection instead

If casting feels unreliable or you need a permanent setup, a wired HDMI connection is more stable and doesn't depend on Wi-Fi. On Windows, use an HDMI cable directly from your computer to the TV (or to the Chromecast's HDMI port if you want to keep the Chromecast plugged in). On Mac, use a USB-C to HDMI or Thunderbolt to HDMI adapter.

Wired connections also have lower latency, meaning less delay between what you do on your keyboard and what appears on screen. This matters if you're gaming or doing video editing. The trade-off is that you're tethered to the TV by a cable, so wireless casting is better if you need to move around the room.

If your TV doesn't have an HDMI port (older TVs sometimes don't), you'll need an adapter that converts HDMI to the input your TV uses—usually composite (RCA) or S-video. These adapters are inexpensive but introduce more potential points of failure, so test before relying on them for important presentations.

Frequently Asked Questions

Can I cast to Chromecast from my phone instead of my computer?

Yes. Android phones and iPhones can both cast to Chromecast using the Google Home app or by tapping the Cast button in apps like YouTube, Netflix, or Google Photos. The process is simpler on phones than on computers because casting is built into Android and supported by most major apps.

What if my Chromecast is on a different Wi-Fi network than my computer?

Casting won't work if they're on different networks. Both devices must be connected to the same Wi-Fi network. If your router broadcasts multiple networks (like a guest network), make sure both your computer and Chromecast are on the main network, not the guest network.

Does casting use a lot of internet bandwidth?

Casting happens over your local Wi-Fi network, not through the internet, so it doesn't use your internet plan's bandwidth. However, if you're streaming video through the cast (like YouTube), that video data does use your internet. The casting itself is just sending your screen image locally.

Can I cast just one window instead of my entire screen?

Windows doesn't offer a built-in way to cast a single window—it mirrors or extends your entire desktop. However, you can minimize other windows or move them off-screen to focus attention on one window, or use full-screen mode in applications like web browsers or video players.

Why does my screen go black when I start casting?

A brief black screen when casting starts is normal—Windows is switching display modes. If the screen stays black, your TV might not be set to the correct HDMI input, or the Chromecast didn't connect properly. Check that your TV is on the HDMI input where the Chromecast is plugged in, then try casting again.