How Many Displays Can You Plug Into Your Mac?

With all of Apple’s Macs having moved well beyond basic HDMI ports into the realm of DisplayPort, USB-C, and Thunderbolt 3, the question of how many displays you can use on a given Mac has started to get a bit confusing.

Although most average users only need a single display, if you’re doing creative work, a second or even third display often comes in handy. This could be to give you a bigger canvas to work on than the built-in display on your 13-inch MacBook Pro, or to handle sophisticated audio and video editing in Logic Pro X or Final Cut Pro X on anything from a Mac mini to Apple’s new powerhouse Mac Pro. Or you may have the need or a specialized solution that involves driving multiple displays for a media or presentation system.

The first thing to keep in mind is that the number of available ports is not directly related to the number of displays that can be driven. While this may be a bit more obvious with multipurpose USB-C and Thunderbolt 3 ports — they can’t all be used for displays on most Macs — Apple has released some confusing configurations in the past. The 2014 Mac mini, for example, offered an HDMI 2.0 port and two mini DisplayPorts. You might understandably think that this configuration of three ports designed explicitly for connecting displays would allow you to drive, well, three displays, but you’d be wrong. It turns out that this particular model of Mac mini provided the three ports to give you options, yet the GPU can still only handle two displays at a time, regardless of how you connected them. So we strongly recommend that you always check out the specs when buying a new Mac rather than making assumptions.

Mac Pro

Of course, the king of the hill right now is the Mac Pro, so it’s probably no big surprise that it can drive up to a dozen 4K displays, but the specifics are a bit more complicated than that, since it’s largely dependent upon which GPUs you choose to put into this highly-configurable Mac.

While Apple normally just publishes the maximum number of displays that a given Mac can drive on the tech specs page for each Mac, the Mac Pro is such a complicated beast that Apple recently shared a dedicated support document that lists all of the possible display configurations for it.

Since you have a choice of three high-end graphics cards in the standard configure-to-order builds, the display configurations get a bit more complicated, but if you opt for the highest-end option — a pair of Radeon Pro Vega II Duo MPX Modules, you will actually be able to drive six Pro Display XDRs, or other compatible 6K displays at 6016 x 3384 resolution.

Mind you, this configuration doesn’t come cheap. Just adding the two highest-end GPUs will bring the price of the baseline Mac Pro up to $16,799 — and that’s leaving every other spec at the bare minimum. The Radeon Pro Vega II Duo cards are $5,600 each, and you’ll still need to drop another $30,000 on the six Pro Display XDRs.

What’s interesting is that, according to Apple’s support document, a single Radeon Pro Vega II Duo MPX will only drive two Pro Display XDRs, just like all of the other GPU options, however plugging in two of them actually triples the number of monitors that are supported. By comparison, pairing up two Radeon Pro Vega II MPX Modules only drives the expected four 6K displays — two per module.

The numbers for 5K displays are almost identical, with the only exception being that a single Radeon Pro Vega II MPX module will let you run three 5K displays, versus two 6K displays.

When it comes to driving 4K displays, however, the numbers increase dramatically, with the baseline configuration able to support up to six 4K displays at 3840 x 2160 resolutions, and either of the dual Radeon Pro Vega II MPX Module configurations — Duo and non-Duo — able to drive twelve 4K displays.

What Apple hasn’t quite made clear in all of this yet, however, is what the specific options are if you choose to mix and match different resolutions — for example if you wanted to connect a single Pro Display XDR as your main canvas and multiple 4K displays to use for other workspaces like palettes and editing tools. Presumably, the numbers should be linear — for example, if the standard GPU configuration (the Radeon Pro 580X) can drive two Pro Display XDRs and six 4K displays, then in theory you should be able to use a single Pro Display XDR and three 4K displays — but Apple hasn’t clarified this situation, so we’d recommend talking to an Apple specialist just to make sure.

Other Macs

As we mentioned earlier, most other Macs have their maximum display configurations listed on their tech specs pages on Apple’s site, usually under a heading like “Video Support.” For example, in addition to the built-in display, Apple’s new 16-inch MacBook Pro can drive up to two more 6K displays or four 4K displays using the Thunderbolt 3 ports, while the 13-inch MacBook Pro and MacBook Air are both limited to a single additional 5K display or two 4K displays.

Since it doesn’t include a built-in display, Apple’s 2018 Mac mini is more generous, offering the ability to connect either one 5K or two 4K displays to the Thunderbolt 3 ports while also driving a standard 4K display via the HDMI 2.0 port, for a total of up to three 4K displays.

External GPUs

As you can see from the example of the Mac Pro, the limitation on the number of displays is based on the GPU that’s installed in each Mac. However, the Mac Pro isn’t the only model that offers more options in this area; any Thunderbolt 3 equipped Mac — which is pretty much all of them these days — can also use an external GPU.

Adding your own external GPU to even something like the diminutive Mac mini or the MacBook Air can offer the ability to connect more displays or drive a 6K display like Apple’s Pro Display XDR. Of course, these external GPUs don’t come cheap, so if you’re looking at a new Mac you might be better off simply spending the money on a model that can natively support more displays, such as going with a 15-inch MacBook Pro instead of the 13-inch version.

USB to HDMI

Although it’s not something we normally recommend, we’d be remiss if we didn’t mention one last option, which is to use a USB to HDMI adapter.

This is not the same thing as a USB-C to HDMI or DisplayPort adapter, which use your Mac’s GPU and are really just changing the connector type. A USB-A to HDMI adapter requires additional drivers to emulate an additional display at a software level, and this naturally has its limitations — they rarely work above 1080p HD, and usually aren’t suitable for animation of video due to the software driver and USB hardware overhead. However, they’re also very inexpensive and can work in situations where you need an extra display that doesn’t require low latency or high resolution, such as an extra display for editing tools, or a “stage display” in a presentation system.