Connect your TV to your computer using HDMI, DisplayPort, or wireless casting

Your TV can work as a second monitor if your computer and TV both support the same connection type. The simplest method is a cable — HDMI works with almost every modern TV and computer, and DisplayPort works with many newer computers and some TVs. If you want to avoid cables, you can use wireless casting through Windows, Mac, or third-party apps, though this adds a small delay that matters for gaming or video editing.

Before you buy a cable or adapter, check what ports your computer actually has. Look at the sides and back of your laptop or the back of your desktop tower. Common ports are HDMI (a flat rectangular shape), USB-C (small oval), DisplayPort (looks like HDMI but with a notch), or Mini DisplayPort (smaller version). Your TV almost certainly has HDMI. If your computer does not have HDMI, you will need an adapter — USB-C to HDMI or DisplayPort to HDMI are cheap and widely available.

Key Takeaways

  • HDMI is the easiest connection method because nearly all computers and TVs have an HDMI port, and a cable costs under $10.
  • Your computer must support extending or mirroring a display — this is built into Windows, Mac, and Linux, but you need to turn it on in settings.
  • TV resolution and refresh rate matter: a 4K TV will display sharper text than a 1080p TV, and 60Hz is standard while 120Hz reduces flicker during fast motion.
  • Extending your display (using the TV as a separate workspace) works better than mirroring (showing the same image on both screens) for productivity.
  • Audio from your computer will play through the TV speakers by default once connected, but you can change this in your sound settings.

Physical connection with HDMI or DisplayPort cable

Plug one end of an HDMI cable into your TV's HDMI port — most TVs have two to four HDMI ports on the back or side, usually labeled HDMI 1, HDMI 2, and so on. Plug the other end into your computer's HDMI port. If your computer does not have HDMI, use a USB-C to HDMI adapter or DisplayPort to HDMI adapter depending on what ports your computer has. Turn on your TV and your computer should detect it within a few seconds.

On Windows, right-click your desktop and select "Display settings." You should see both your main monitor and your TV listed. On Mac, open System Preferences, go to Displays, and both screens should appear. On Linux, open Settings and look for Displays. If your TV does not appear, restart your computer — sometimes the connection needs a restart to register.

Choose between extending and mirroring your display

Extending means your TV becomes a separate workspace. Your mouse and windows can move between your main monitor and the TV. This is useful if you want to watch a video on the TV while working on your main monitor, or if you want extra screen space for spreadsheets or code. Mirroring means both screens show the exact same image — useful for presentations or if you want to show someone else what you are doing, but it wastes the TV's screen space.

On Windows, open Display settings, scroll down, and under "Multiple displays" select "Extend these displays." On Mac, open System Preferences > Displays, click the Arrangement tab, and make sure "Mirror Displays" is unchecked. On Linux, the option is usually in Settings > Displays with a checkbox for "Mirror." Once you extend, you can drag windows between screens by clicking and dragging the title bar.

If you extend your display, you need to tell your computer which screen is your main one. In Windows Display settings, click on the screen you want as primary and check "Make this my main display." On Mac, drag the white bar in the Arrangement tab to the screen you want as primary. Your main screen is where new windows and dialog boxes will open.

Adjust resolution and refresh rate for clarity and smoothness

Once your TV is connected, your computer may automatically set it to a lower resolution than it can handle. In Windows Display settings, scroll down to "Display resolution" and select the highest option available — usually 1920 × 1080 (called 1080p) for older TVs or 3840 × 2160 (called 4K) for newer ones. Higher resolution means sharper text and images. On Mac, open System Preferences > Displays and click "Scaled," then choose the resolution you prefer. On Linux, the option is usually in Settings > Displays.

Refresh rate is how many times per second the screen redraws the image. Most TVs run at 60Hz, which is fine for everyday use. Some newer TVs support 120Hz, which makes fast motion smoother but uses more power. On Windows, you can check and change refresh rate in Display settings by clicking "Advanced display settings" and looking for "Refresh rate." On Mac, this is in System Preferences > Displays > Refresh Rate. On Linux, it is usually in Settings > Displays.

If text looks blurry on your TV, try lowering the resolution one step. TVs are designed to be viewed from farther away than monitors, so sometimes a lower resolution actually looks clearer at normal viewing distance. You can also increase text size in your operating system settings — on Windows, go to Display settings and adjust "Scale," and on Mac, go to System Preferences > Displays and choose a larger scaled resolution.

Wireless connection using casting or AirPlay

If you do not want to run a cable, you can cast your display wirelessly. On Windows 10 and 11, press Windows key + K to open the Quick Settings panel, click "Connect," and select your TV if it appears in the list. Your TV must support Miracast, which most modern TVs do. On Mac, click the Control Center in the top right, select "Screen Mirroring," and choose your TV — your TV must support AirPlay, which most Apple TVs and newer Samsung and LG TVs do.

Wireless casting is slower than a cable connection and adds a delay of about 100 to 200 milliseconds, which you will notice if you are gaming, editing video, or doing anything that requires precise timing. For watching videos or working with documents, the delay is not noticeable. If your TV does not appear in the casting menu, make sure it is on the same WiFi network as your computer and that casting is turned on in your TV's settings — the exact steps vary by TV brand, but it is usually under Network or Connectivity settings.

Route audio to your TV speakers or keep it on your computer

Once your TV is connected, your computer will usually send audio through the TV's speakers automatically. If you want to hear sound from your computer speakers instead, you need to change your audio output. On Windows, right-click the volume icon in the taskbar, select "Open Volume mixer," and under "Advanced" change the default playback device from your TV to your speakers or headphones. On Mac, open System Preferences > Sound, click the Output tab, and select your preferred speaker.

If you are extending your display and want different audio on each screen — for example, watching a video on the TV while listening to music on your computer speakers — you will need to use your TV's remote to control the TV's volume separately. Most operating systems only let you choose one default audio output at a time. Some advanced audio software can split audio between devices, but this requires additional setup.

Troubleshoot common connection problems

If your TV does not appear after connecting the cable, try these steps in order: first, unplug the cable from both ends and plug it back in; second, restart your computer; third, restart your TV; fourth, try a different HDMI port on your TV. If you are using an adapter, try a different adapter — adapters sometimes fail without obvious signs.

If your TV appears in settings but shows a black screen, your computer may not support the resolution your TV is trying to use. Lower the resolution in Display settings to 1920 × 1080 and see if the image appears. If the image appears but looks stretched or has black bars, your TV's aspect ratio setting may be wrong — check your TV's picture settings for an option called "Aspect Ratio" or "Zoom" and set it to "Full" or "16:9."

If wireless casting keeps disconnecting, move your computer closer to your TV and router, or switch to a wired HDMI connection. Wireless casting is sensitive to interference from other WiFi networks and devices. If you are using an older TV that does not support Miracast or AirPlay, you can buy a cheap casting device like a Chromecast or Fire Stick that plugs into your TV's HDMI port and adds wireless casting support.

Frequently Asked Questions

Can I use any TV as a second monitor?

Any TV with an HDMI port can work as a second monitor. Older TVs without HDMI can work with an adapter, but this is rare now. Smart TVs, regular TVs, and even some projectors all work the same way — they just need a way to receive a video signal from your computer.

Will using a TV as a monitor damage it?

No. TVs are designed to display video for hours at a time. The only concern is heat — make sure your TV has space around it for air to circulate, and do not cover the vents. If your TV gets very hot, turn it off and let it cool down.

Why does my TV show a different color than my main monitor?

TVs and monitors use different color settings by default. You can adjust your TV's picture settings using its remote — look for options like "Color," "Saturation," or "Picture Mode." Set it to "Standard" or "Movie" mode for more accurate colors. You can also adjust color in your computer's display settings, though this is less common.

Can I extend my display to more than one TV?

Yes, if your computer has multiple video ports or you use USB adapters. Windows and Mac both support three or more displays at once. Each display needs its own cable or wireless connection. Keep in mind that using multiple displays uses more power and can slow down your computer slightly.

What if my computer does not detect my TV?

First, check that the cable is plugged in firmly on both ends. Second, make sure your TV is on and set to the correct HDMI input — use your TV remote to switch inputs if needed. Third, restart your computer. If it still does not work, try a different HDMI cable or a different HDMI port on your TV.