The basic connection: what cable you need depends on your ports

Your computer connects to a TV the same way it connects to a monitor — through a video cable that carries the picture from your graphics card to the screen. The cable you use depends on which ports both your computer and TV have. Most modern TVs have HDMI ports, which is the simplest route. If your computer is older or uses a laptop with USB-C, you may need an adapter.

Start by looking at the back or sides of your computer. Desktop computers usually have ports on the graphics card itself (the back panel). Laptops have ports on the sides. Write down what you see: HDMI looks like a flat rectangle with angled sides. DisplayPort is smaller and rectangular. USB-C is oval and reversible. VGA is a blue trapezoid with three rows of holes (older computers only). Then look at your TV's ports, usually on the back or side panel.

If both your computer and TV have HDMI, buy an HDMI cable and you are done. If they do not match, you need an adapter that converts one type to another. Adapters cost between $10 and $30 and work in one direction only — check which end plugs into which device before you buy.

Key Takeaways

  • HDMI is the standard connection for modern computers and TVs, and an HDMI cable is the simplest option if both devices have the port.
  • If your ports do not match, you need an adapter that converts from your computer's output to your TV's input — adapters are directional and cost $10 to $30.
  • After plugging in the cable, your TV may not show a picture until you switch to the correct input using the TV remote or on-screen menu.
  • Windows and Mac computers may need you to adjust display settings so the TV shows the full picture instead of a stretched or cut-off version.
  • Audio does not always travel through the video cable — you may need a separate audio cable or to change your computer's sound output in settings.

Finding and switching to the correct TV input

Plugging in the cable does not automatically make the picture appear. Your TV has multiple inputs (HDMI 1, HDMI 2, HDMI 3, and others), and it is showing one of them right now. You need to tell it which input your computer is plugged into.

Pick up your TV remote and look for a button labeled "Input," "Source," or "HDMI." Press it. A menu will appear showing all the inputs available on your TV. Find the one your cable is plugged into — if you plugged the cable into the HDMI port on the left side of the TV, it is probably HDMI 1 or HDMI 2. Select it with the arrow buttons and press Enter. Your computer's screen should appear on the TV.

If nothing appears, try the other HDMI inputs one at a time. If you still see nothing, unplug the cable, wait 10 seconds, and plug it back in. Then try the input menu again. If the TV shows "No Signal," the cable may be loose or the port may be damaged.

Adjusting the picture size and position on Windows

Once the picture appears, it may not fill the screen correctly. It might be stretched, squeezed, cut off at the edges, or surrounded by black bars. This happens because your computer and TV have different aspect ratios — the relationship between width and height.

On Windows, right-click on the desktop and select "Display settings." Scroll down to the "Scale and layout" section. If the text and icons look too small or too large, change the percentage. Most people use 100 percent, but TVs often need 125 or 150 percent because you sit farther away. Below that, find "Display resolution" and make sure it matches your TV's native resolution — for most modern TVs, this is 1920 by 1080 or 3840 by 2160 (4K). If the picture is still cut off, scroll down to "Advanced display settings" and look for an option called "Overscan" or "Underscan." Turning overscan off usually fixes edges that are missing.

If the picture is still wrong, the problem may be in your TV's settings, not your computer. On your TV remote, look for a menu button and search for "Picture," "Display," or "Aspect Ratio." Try changing the aspect ratio to "Full" or "Fit to Screen" instead of "Zoom" or "Stretch."

Adjusting the picture size and position on Mac

On a Mac, click the Apple menu in the top-left corner and select "System Settings." Click "Displays" in the sidebar. You should see your TV listed as a second display. Click on it, then look for "Resolution" or "Scaled." If the text looks too small, select a lower resolution number — this makes everything larger. If the picture is cut off at the edges, look for an option called "Underscan" or a slider labeled "Brightness" that actually controls overscan. Moving it left usually brings back the missing edges.

If your Mac does not recognize the TV at all, try unplugging the cable and plugging it back in. If you are using an adapter, make sure it is plugged in firmly on both ends. Some older adapters do not work with newer Macs — if this happens, you may need a different adapter or cable.

Getting sound to work through your TV

Video and audio are not always connected. Your computer may send the picture through HDMI but not the sound, or it may send sound to your computer's speakers instead of the TV's speakers.

On Windows, right-click the speaker icon in the bottom-right corner of the taskbar and select "Open Volume mixer." Look for your TV in the list of devices. If it is there, click on it and select "Set as default device." If it is not there, right-click on an empty space and select "Show disabled devices." If your TV appears in that list, right-click it and select "Enable." Then set it as the default.

On Mac, click the Apple menu and select "System Settings." Click "Sound" in the sidebar. Under "Output," look for your TV in the list. Click on it. If your TV does not appear, make sure the HDMI cable is plugged in and the TV is on, then wait a few seconds and check again.

If you do not want sound coming from the TV, you can leave your computer's audio going to your speakers or headphones while the picture goes to the TV. This is useful if your TV's speakers are poor quality or if you want to watch quietly without disturbing others.

Using your TV as your main display or extending your desktop

When you connect a TV to your computer, you have two choices: mirror your display (show the same thing on both screens) or extend your display (use the TV as extra space). Most computers default to mirroring.

On Windows, right-click on the desktop and select "Display settings." Scroll down to "Multiple displays." You will see three options: "Extend these displays" (use the TV as extra space), "Duplicate these displays" (show the same thing on both), or "Show only on 1" or "Show only on 2" (use just one screen). Select what you want. If you choose extend, you can drag windows between your computer screen and the TV.

On Mac, click the Apple menu and select "System Settings." Click "Displays" in the sidebar. At the bottom, you will see options for how to arrange your displays. Click "Arrangement" to see a visual layout. You can drag the display boxes to match how your screens are physically positioned, which makes moving your mouse between them feel natural.

Troubleshooting when the picture does not appear

If you have plugged everything in and switched to the correct input but still see nothing, work through these steps in order.

First, check the cable itself. Unplug it from both ends, look inside the connectors for bent pins or damage, and plug it back in firmly. Make sure it is plugged into a port on your graphics card (on desktops) or the correct side of your laptop, not into a USB port by mistake.

Second, restart your computer. Many connection problems fix themselves after a restart. While the computer is restarting, turn off your TV and turn it back on too.

Third, check your computer's display settings. On Windows, press Windows key + P to open the projection menu and select "Extend" or "Duplicate." On Mac, go to System Settings > Displays and make sure the TV is listed. If it is not, the computer does not recognize it yet — wait 30 seconds and check again.

Fourth, if you are using an adapter, try a different one. Adapters fail frequently, and a $15 replacement is cheaper than troubleshooting for hours. If you have access to another computer, test your TV with that computer to see if the problem is the TV or your computer.

If none of these steps work, the TV's HDMI port may be damaged, or your computer's graphics card may not support the resolution the TV is requesting. Contact the TV manufacturer's support line with the model number (usually on a sticker on the back) and describe what you see when you plug in the cable.

Frequently Asked Questions

Can I use a wireless connection instead of a cable?

Yes, if your computer and TV both support it. Windows computers can use Miracast, and Macs can use AirPlay. Both are built into the operating system. The picture quality is usually lower than a cable, and there can be a slight delay, but they work well for presentations or watching videos. Look in your display settings for a "Connect to a wireless display" option.

What if my TV is in another room?

HDMI cables work up to about 50 feet, but the signal gets weaker over distance. For longer runs, use an HDMI extender (a device that boosts the signal) or run the cable through your walls with a professional installer. Wireless options like Miracast or AirPlay work through walls and are simpler if your TV supports them.

Do I need a special cable for 4K or high refresh rate?

Standard HDMI cables work for 4K, but older cables may not support high refresh rates (above 60 Hz). If you are buying a new cable for a 4K TV or a gaming setup, look for one labeled "HDMI 2.1" or "Ultra High Speed HDMI." They cost a few dollars more and future-proof your setup.

Will connecting to a TV slow down my computer?

No. The TV is just a display — it does not affect your computer's speed or performance. Your computer works the same whether it is plugged into a monitor or a TV.

Can I use my TV as my only display and put my laptop away?

Yes. You can use the TV as your main display and close your laptop, or disconnect your laptop entirely. Some people use a wireless keyboard and mouse to control their computer from across the room while the TV shows the screen. This works well for streaming, browsing, or presentations.