The cables and ports you need depend on which Mac and monitor you have
Your Mac connects to a monitor through a video cable, but the type of cable and port varies by model year. Newer Macs use USB-C or Thunderbolt ports; older ones use Mini DisplayPort, HDMI, or VGA. Your monitor likely has HDMI, DisplayPort, or USB-C built in. The first step is identifying which ports exist on both your Mac and your monitor, then buying or finding the right cable to match them.
If your Mac and monitor don't share a port type, you'll need an adapter. These are inexpensive (usually $15 to $40) and widely available. The wrong adapter won't damage anything—it straightforward won't work—so there's no risk in trying one if you're unsure.
Key Takeaways
- Check the ports on the back or sides of your Mac and monitor to identify which cable type you need: USB-C, Thunderbolt, HDMI, DisplayPort, or Mini DisplayPort.
- If your Mac and monitor don't match, buy an adapter that converts from your Mac's port to your monitor's input (for example, USB-C to HDMI).
- Plug the cable into both devices, then your Mac should detect the monitor automatically within a few seconds.
- If the monitor doesn't appear, restart your Mac or try a different cable, as connection problems are usually hardware-related, not settings-related.
- You can adjust resolution and brightness in System Settings under Displays once the monitor is connected.
Identifying your Mac's video ports
Look at the sides of your Mac—not the back, as desktop Macs are less common now. On a MacBook, you'll see small ports along the edges. On a Mac mini or iMac, check the rear panel. The ports you're looking for are small and rectangular.
USB-C ports are oval and flat, about the size of a grain of rice. They're on all modern MacBook Air and MacBook Pro models (2016 and newer). Thunderbolt ports look identical to USB-C but have a small lightning bolt symbol next to them; they're on newer MacBook Pro models and some Mac minis. HDMI ports are larger and rectangular, found on some older MacBook Pro models and Mac minis. Mini DisplayPort looks like a small flat rectangle with a notch; it's on older MacBook Air and MacBook Pro models (pre-2016). If you have a very old Mac, you might see a VGA port, which is a larger rectangular connector with small holes.
If you're unsure which Mac you have, click the Apple menu in the top-left corner, select "About This Mac," and note the model name and year. Then search "[your model] ports" to see a diagram.
Identifying your monitor's input ports
Look at the back of your monitor for input ports. Most modern monitors have at least one of these: HDMI (large rectangular port, very common), DisplayPort (smaller rectangular port with a notch, common on newer monitors), or USB-C (oval and flat, found on newer premium monitors). Some monitors also have VGA (older, with small holes) or DVI (rectangular with pins).
If your monitor came with a cable, that cable is already the right type for your monitor. Check what port it plugs into on the monitor's end, and you've identified your monitor's input type. If you've lost the cable, the manual or the monitor's spec sheet (often a sticker on the back) will list which ports are available.
Buying or finding the right cable or adapter
Once you know both port types, you need a cable that matches. If both your Mac and monitor have the same port type (for example, both have USB-C), you can use a standard cable for that port. If they don't match, you need an adapter.
Common adapters include USB-C to HDMI, USB-C to DisplayPort, Thunderbolt to HDMI, Mini DisplayPort to HDMI, and HDMI to DisplayPort. Search for the exact combination on Amazon, Best Buy, or any electronics retailer. Apple also sells official adapters on their website, though third-party adapters work just as well and cost less. Make sure the adapter is rated for video, not just data transfer.
If you're connecting a USB-C monitor directly to a USB-C Mac, you may not need a separate cable at all—the monitor's built-in USB-C cable might work. Check the monitor's manual first.
Plugging in and powering on
Connect the cable or adapter to your Mac's port first, then to your monitor's input port. Plug the monitor into power and turn it on. Your Mac should detect the monitor within a few seconds. You'll see the monitor light up, and your Mac's screen may briefly go black as it switches to the external display.
If you're using a MacBook, you can keep it open or close the lid—closing the lid puts the MacBook to sleep, but the external monitor will stay active if you have a mouse and keyboard connected. If you want to use the MacBook's screen and the external monitor at the same time, leave the lid open.
What to do if the monitor doesn't appear
If you plug everything in and the monitor stays blank, the problem is almost always the cable or adapter, not your Mac's settings. Try these steps in order.
First, unplug the cable from both ends and plug it back in firmly. Sometimes a loose connection is the only issue. Second, try a different cable or adapter if you have one available—borrow one from a friend or buy a cheap one to test. Third, restart your Mac: click the Apple menu, select "Restart," and wait for it to boot up with the monitor connected. Fourth, if you're using an adapter, make sure it's designed for video output, not just charging or data.
If the monitor still doesn't work after trying a different cable and restarting, the monitor's input port or your Mac's video port may be damaged. In that case, contact the monitor's manufacturer or take your Mac to an Apple Store.
Adjusting resolution and display settings
Once your monitor is connected and working, you can adjust how it looks. Click the Apple menu, select "System Settings," then click "Displays" in the sidebar. You'll see options for resolution, refresh rate, and brightness.
Resolution controls how sharp the text and images appear. Higher resolution means smaller text but more screen space; lower resolution means larger text but less space. Your monitor has a native resolution (the sharpest setting), which macOS usually selects automatically. If text looks blurry, try changing the resolution.
Refresh rate is how many times per second the monitor redraws the image. Most monitors are 60 Hz, which is fine for everyday work. Gaming monitors may offer 120 Hz or higher. Brightness is self-explanatory and can be adjusted here or sometimes with buttons on the monitor itself.
Frequently Asked Questions
Can I connect two external monitors to my Mac?
Yes, but it depends on your Mac model. Most modern MacBooks and Mac minis support two external displays. Older models may support only one. Check your Mac's tech specs by clicking the Apple menu, selecting "About This Mac," then searching "[your model] external displays" online to confirm how many your Mac supports.
Why is my monitor showing a blurry or stretched image?
This usually means the resolution is set incorrectly. Go to System Settings > Displays and try a different resolution. The native resolution (often labeled "Default") will look sharpest. If text is too small, you can also adjust the scaling option in the same menu.
Do I need to buy an Apple adapter, or will a third-party one work?
Third-party adapters work just as well as Apple's official ones for video output. Buy whichever is cheaper and has good reviews. The only exception is if you need charging and video at the same time—some third-party adapters don't support both, so check the product description.
What if my monitor has USB ports—can I use those to connect to my Mac?
No. USB ports on a monitor are for connecting peripherals like keyboards or printers to your Mac through the monitor. They don't carry video. You still need a video cable (HDMI, DisplayPort, or USB-C) to display an image on the monitor.
Can I use an HDMI cable to connect my Mac to a TV instead of a monitor?
Yes. TVs have HDMI ports just like monitors do. Use the same cable or adapter you would for a monitor. The TV will work as a display, though it may not be as sharp as a monitor at close range because TVs are designed to be viewed from farther away.