One of the Mac’s greatest long-term advantages has been the ease of attaching external monitors. The attachment connector type, resolutions supported, and total quantity has varied over time, but it’s a persistently easy task.
Or it was. Apple has introduced USB 3 over USB C (12-inch MacBook now discontinued), Thunderbolt 3 which uses USB C (and supports many types of adapters), as well as the Apple silicon M series processor models. Some Macs still have video-specific connectors. In the past, this included DVI (multiple forms), Mini DisplayPort and DisplayPort over Thunderbolt 2.
More recently, HDMI 2.0 became the only remaining video connector that’s not USB-C. Apple built HDMI into many Intel models as well as on the M1 Mac mini, the 14-inch and 16-inch M1 Pro/Max MacBook Pro, and the Mac Studio.
For many readers, the process of figuring out how many Macs can take what monitors has been akin calculating calculus. It was based on our mailbag.
(Have you got a monitor with DVI, Mini DisplayPort or Thunderbolt 2? Check out our guide starting in 2020 on how to determine what you have and which kind of adapter you need. You can use your iMac as an external display monitor. Only iMacs from 2009 to mid 2014 qualify. See “Troubleshooting tips when using an old iMac to display external information for a Thunderbolt 3 Mac.”)
Here’s the matchup for Macs of the last few generations, starting with the newest, not including the internal display for iMac and Mac laptops. Except where otherwise noted, connections are made via a USB C connection.
These are the resolutions for your reference:
- 4K UHD: 3840×2160 pixels
- 4K: 4096 wide, with common variations that include 4096×2160 or 4096×2304 pixels
- 5K: 5120×2880 pixels
- 6K: 6016×3384 pixels
For each configuration, or set of options the highest supported resolution is listed. But you can use a monitor with a lower resolution. The M1 Mac mini supports up to 6K via USB-C. However, you can also plug in a 4K UHD monitor.
M-series Mac Monitor Options
The majority of M1 or M2 Macs can only accept one external monitor. The Mac mini, however, allows for two. Despite many reader questions, there’s no adapter or trickery you can do using Apple equipment to add an additional display beyond the level Apple supports.* The video circuitry simply isn’t there.
These are the options, sorted by display choice:
- M1 and M2 MacBook Airs, 13-inch MacBook Pros, M1 iMac: One external display at up to 6K resolution
- M1 Mac mini One at up to 6K over USB-C and one at up to 4K over HDMI 2.0
(*You can use DisplayLink technology is used in hardwareYou can add additional monitors using USB 3. This requires the installation of a kernel driver from the company. Check out our Mac-compatible review StarTech USB 3.0-to HDMI Adapter with DisplayLink.)
Options for M1 Pro and Max monitors
Apple has dramatically increased the number of professional-level models’ display options with the M1 Pro and M1 Ultra chip announcements in October 2021 and March 2022.
- MacBook Pro, 14-inch and 16-inch with M1 ProTwo external displays, one with USB-C connectivity and one with HDMI 2.0 at 4K each.
- MacBook Pro 14-inch, 16-inch MacBook Pro with the M1 Max:Three external displays up to 6K with USB-C, and one up to 4K with HDMI 2.0
- Mac Studio with M1 Max, M1 Ultra or Mac Studio:Four displays up to 6K using USB-C ports with Thunderbolt 4 or one up to 4K using HDMI 2.0
The Mac Studio’s M1 Max configuration includes two USB 3 front-facing USB-C ports that cannot be used with DisplayPort adapters; the M1 Ultra model upgrades those to Thunderbolt 4, which can be used with a standard USB-C DisplayPort adapter. This doesn’t decrease the number of monitors that can be attached, but it might requires an external Thunderbolt 4 dock to have enough USB-C connectors free for all your purposes.
Intel Mac with Thunderbolt 3 and USB 3/Thunderbolt 3 Monitor Options
Thunderbolt 3 enabled Intel Macs had a narrower selection of external monitor configurations. These are the options for each Thunderbolt 3 model, and the 12-inch MacBook with USB 3 vs USB-C.
- 21.5-inch iMac: One 5K display or two 4K UHD or 4K displays
- 27-inch iMac (standard video card), 13-inch MacBook Pro: Either one 5K or 6K display or two 4K UHD or 4K displays
- 27 inch iMac (AMD Radeon Pro 55700 or AMD Radeon Pro5700 XT). Up to two 4K UHD, 4K, 5K, or 6K displays
- MacBook Pro 16 inch: Up to two 5K or 6K display or up to four 4K UHD or 4K displays
- Mac: One 5K display via USB-C or up to three 4K displays with a combination of USB-C and HDMI 2.0 ports
- Mac Pro Depending on the video card, it ranges from one 5K or 6K display or up to four 4K displays through up to four 5K or 6K displays or up to eight 4K displays
- 12-inch MacBook: One 4K display
Ask Mac 911
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