You can be excused if you don’t know off the top of your head how many external displays your MacBook supports. The number varies by model, processor version, and even whether the laptop is open or closed. Still, there’s a good chance it’s more than you think.

Now that notebooks with the new M4 family of processors are available, here’s an updated guide to how many external screens you can attach to your MacBook.

Confusion stems from Apple silicon transition

External displays make MacBook users more productive. More screens mean more space to work in, and that can be critical when you’re using a 14-inch notebook. Even a 16-inch screen is small compared to a desktop monitor.

All MacBooks offer second-screen support. So the question is, which ones can handle more than one?

It’s a question that only became important when Apple brought out its own Mac processors in 2020. Before then, Intel-based Pro models offered plenty of additional screens. But the first MacBook Pro with Apple silicon supported only a single external display. That’s because it used an Apple M1 processor. The 2020 MBP was part of the Intel-to-Apple transition and was essentially an Intel model with a new chip plugged in. A chip that wasn’t completely up to the job of powering a professional-class laptop.

Since then, the number has grown tremendously. It currently tops out at four… with the right model and processor.

MacBook external display support varies by processor

While we talk about the M1, M2, etc., keep in mind that these each of these is a family of processors. There are Pro, Max and even sometime Ultra versions of the chips. The number of CPU band GPU cores varies, and — what’s important for this discussion — the number of external displays supported.

M1 family

The M1 was great for the consumer-oriented 2020 MacBook Air. But it was never intended for pro-grade computers, and thus only supports one external display. But it was the best Apple silicon available in 2020, so it went into the MacBook Pro released that year, too.

As soon as Apple began bringing out notebooks with the M1 Pro and M1 Max chips, the limitation disappeared.  These were designed for professionals. That includes support for multiple additional displays. Both the 14-inch and 16-inch models can connect to up to three.

M2 family

This all started over again with the Apple M2 released in mid-2022. This is a consumer-focused processor and supports only a single additional display with a 6K resolution at 60Hz. That makes it right for the 13-inch MacBook Air from 2022 and the 15-inch model from summer 2023.

But MacBook Pros that run the M2 Pro and M2 Max can connect to many more screens. The 14-inch and 16-inch MacBook Pro from early 2023 can handle either two or four depending on whether they have a Pro or the Max version of the processor.

To keep things confusing, there’s also a throw-back 13-inch MBP that Apple released in summer 2022. It has a basic M2, not a Pro or Max, so it offers only a single second screen, not more.

M3 family

The cycle repeats with the M3 family introduced in October 2023, but this time with a twist. The basic M3 in the 2024 MacBook Air supports two displays. With the screen open, that’s the internal and an external screen with up to 6K resolution at 60Hz. But close the notebook and this version of the MacBook Air supports a second external display with up to 5K resolution at 60Hz.

MBPs with M3 Pro support two displays up to 6K at 60Hz. Go with the M3 Max version instead, and the notebook supports up to four displays (three of these at 6K, one at 4K).

But because nothing can be simple, Apple also introduced a version of the MacBook Pro in late 2023  with the basic M3 processor. This model supports only a single external display.

M4 family

With November’s launch of the 2024 MacBook Pro, it’s deja vu all over again. The only difference this time is that an M4-based MacBook Air isn’t on the market yet — it’s expected in early 2025. But when it launches, expect it to have the basic M4 and support either one or two external monitors depending on whether the notebook is open or closed, just like the M3-equipped version.

And the new MacBook Pro with the more powerful M4 Pro supports two external displays with up to 6K resolution at 60Hz over Thunderbolt, or one external display with up to 6K at 60Hz over Thunderbolt plus a second display with up to 4K at 144Hz over HDMI. Alternatively, go instead with one external display at 8K and 60Hz or one external display at 4K and 240Hz over HDMI.

The M4 Max version offers even more: it can handle up to four external displays. One option is three external displays with 6K at 60Hz over Thunderbolt and a fourth at 4K at 144Hz over HDMI. Another option is three external displays. Two of these can be 6K at 60Hz over Thunderbolt and the third can be either 8K at 60Hz or 4K at 240Hz over HDMI.

Thankfully, there’s no version of the MBP with a basic M4 processor.

There’s no doubt this is confusing. It’s bad enough that Apple has a support document just to lay out how many external screens each MacBook Pro can connect to.

A nomenclature problem

Part of the external display confusion stems from the way people tend to refer to Apple processors. “M1” is a single processor but the term also is used sometimes as shorthand for a family of processors: M1, M1 Pro, M1 Max and M1 Ultra. The same goes for M2 and M3 and M4.

It leads to confusion. It’s easy to refer to an “M3 MacBook Pro” when the notebook is really an M3 Pro MBP. And someone can read “M3 MacBook Pro” and, because the basic M3 supports only one extra display, assume that every notebook with a processor from the M3 family has the same limitation.

Spread the word

The basic M1-based MacBook Pro was popular and a many are still in use. Because it was limited to only one external monitor, it’s possible some people think this is true of all M-series MacBooks. It’s possible you know someone who fits in this category.

Also, I’ve seen criticism of the M4 MacBook Pro because it only supports only two external screens. But that’s not true: the M4 Max version supports four. Feel free to correct people confused about this.