What Google Cast Does and How to Start

Google Cast is the technology that lets you send video, music, photos, or your entire screen from your phone, tablet, or computer to a TV or speaker. You don't need a cable or remote control—once your device and your TV are on the same Wi-Fi network, you can tap a Cast button in most apps and watch on the big screen within seconds.

The Cast button looks like a rectangle with curved lines in the corner (like a TV with a signal). You'll find it in apps like YouTube, Netflix, Spotify, Google Photos, and Chrome. If you don't see it, the app may not support Cast yet, or your device may not be connected to Wi-Fi.

Before you start, make sure your TV has a Chromecast device plugged in, or that your TV is a Chromecast built-in TV (a TV with Cast technology built into it from the factory). Your phone, tablet, or computer must be on the same Wi-Fi network as your TV.

Key Takeaways

  • Google Cast works only when your phone, tablet, or computer and your TV are connected to the same Wi-Fi network.
  • The Cast button appears in most streaming apps—tap it, select your TV, and the content plays on your screen within seconds.
  • You can cast your entire screen (called screen mirroring) from Android phones and Windows computers, or use Chrome on any computer.
  • If the Cast button doesn't appear, restart your Wi-Fi router, forget and rejoin the network, or restart the app.
  • Casting stops when you leave the Wi-Fi network or turn off your TV, and you can control playback from your phone while casting.

Casting Video and Music from Apps

Open any app that supports Cast—YouTube, Netflix, Disney+, Hulu, Spotify, or Google Play Music are common ones. Start playing the video or song you want to watch or listen to. Look for the Cast button (the rectangle with curved lines) in the top or bottom corner of the app.

Tap the Cast button. A list of available devices will appear. Select your TV or speaker from the list. The content will start playing on your TV within a few seconds, and you can control it from your phone—pause, rewind, change the volume, or skip to the next song. Your phone screen can go dark or you can use other apps; the Cast will keep playing.

If the Cast button doesn't show up, check that your phone and TV are on the same Wi-Fi network. Restart the app, restart your phone, or restart your Wi-Fi router. Some apps require you to be signed in to your Google account before Cast appears.

Screen Mirroring from Your Phone or Tablet

Screen mirroring sends everything on your phone or tablet screen to your TV—not just one app, but your whole display. This is useful for showing photos, playing games, or using apps that don't have a Cast button built in.

On Android phones and tablets, swipe down from the top of the screen twice to open Quick Settings. Look for "Cast" or "Screen cast" (the name varies by phone maker). Tap it, select your TV, and your screen will appear on the TV. To stop, tap the Cast button again and select "Disconnect."

On iPhones and iPads, screen mirroring works differently—it's called AirPlay, not Cast, and it requires an Apple TV or an AirPlay-compatible TV. Google Cast does not work with iPhones or iPads for screen mirroring.

Casting from Your Computer or Laptop

On a Windows computer, you can cast your entire screen or just one window. Open the Action Center (click the icon in the bottom right corner of your taskbar that looks like a speech bubble). Click "Connect" or "Project," then select your TV from the list. Your screen will appear on the TV.

On a Mac, Google Cast does not work for screen mirroring. Use AirPlay instead if you have an Apple TV or AirPlay-compatible TV.

On any computer (Windows, Mac, or Linux), you can cast from the Chrome browser. Open Chrome, click the three-dot menu in the top right, select "Cast," choose your TV, and then select "Cast tab" to send just the browser tab, or "Cast desktop" to send your entire screen. This works for any website or video player that runs in Chrome.

Troubleshooting When Cast Doesn't Work

If the Cast button doesn't appear or your device won't connect, start with the basics: make sure your phone, tablet, or computer and your TV are on the same Wi-Fi network. Check that your Chromecast device is plugged in and powered on (look for a light on the device). Restart your Wi-Fi router by unplugging it for 30 seconds, then plugging it back in.

If that doesn't work, forget the Wi-Fi network on your phone and rejoin it. On Android, go to Settings > Network & Internet > Wi-Fi, long-press the network name, and tap "Forget." Then tap the network again and enter your password. On Windows, go to Settings > Network & Internet > Wi-Fi > Manage Known Networks, select your network, and click "Forget." Rejoin the network and try casting again.

Restart the app you're trying to cast from. If the Cast button still doesn't appear, the app may not support Cast yet. Restart your phone or computer. If your TV is a Chromecast built-in TV, check the TV's settings to make sure Cast is turned on (the location varies by TV brand).

If you can see your TV in the Cast list but it won't connect, restart your Chromecast device by unplugging it for 10 seconds. If the problem persists, restart your TV as well.

What Happens When You Cast

When you cast, your phone or computer sends a signal to your TV telling it what to play. The TV then connects directly to the internet and streams the content itself—your phone is not streaming the video to the TV. This means you can lock your phone, use other apps, or even leave the room, and the Cast will keep playing.

The Cast will stop if you turn off your TV, unplug your Chromecast device, or disconnect from Wi-Fi. If you leave your Wi-Fi network (for example, by going outside), the Cast will pause or stop. When you come back and rejoin the network, you can resume casting.

You can control playback from your phone while casting—pause, play, rewind, skip, or change the volume. Some apps let you adjust brightness or subtitles from your phone as well. If someone else on your network tries to cast to the same TV, they can take over, so keep that in mind if you're in a shared space.

Casting to Multiple Speakers

If you have multiple speakers or displays on the same Wi-Fi network, you can cast to more than one at a time. Open the Cast button, and you'll see a list of all available devices. Select one, start playing, then open the Cast button again and select another device. Both will play the same content at the same time.

This works well for music—you can play the same song in your kitchen and living room at once. For video, both screens will show the same thing, so it's less useful unless you're trying to watch on two TVs in different rooms.

Frequently Asked Questions

Do I need a Google account to use Cast?

You need to be signed into a Google account on your phone, tablet, or computer to cast from most apps. Your TV does not need a Google account—it just needs to be on the same Wi-Fi network. Some apps like YouTube require you to be signed in before the Cast button appears.

Can I cast if I'm not home?

No. Cast only works when your device and your TV are on the same Wi-Fi network. If you're away from home, you cannot cast to your home TV. Some apps like YouTube TV or Google Play Movies let you read content to watch offline, but that's different from casting.

Will casting use a lot of data?

Casting uses your Wi-Fi network, not your phone's data plan. If you're on Wi-Fi at home, casting won't count against any data limit. If you're casting from a mobile hotspot, it will use data from that hotspot's plan.

What if my TV doesn't have a Chromecast device?

You can buy a Chromecast device separately and plug it into your TV's HDMI port. Chromecast devices are small and inexpensive. Alternatively, some newer TVs have Chromecast built in from the factory—check your TV's manual or settings to see if yours does.

Can I cast while someone else is using the TV?

Yes, but whoever casts last will take over the screen. If you start casting a movie and someone else casts a different show, their show will replace yours. You can pause or stop your cast from your phone to let someone else use the TV.