Not all ethernet adapters are created equal: here's what to look for on a Mac

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Summary

• Most people use Wi-Fi and that's fine. But if you want a wired connection, the adapter you use matters.

• Some ethernet adapters make your Mac do extra work to process network traffic, which can actually slow things down.

• Others handle more of that work themselves, leaving your Mac free to run normally.

• You can check which type you have in about 30 seconds using System Report.

• If you need an upgrade, I recommend the Plugable USB-C and USB to 2.5G Ethernet Adapter for most people, or the StarTech USB4 10GbE Ethernet Adapter if you need 10GbE.

The vast majority of my clients use Wi-Fi, and that's completely fine. For everyday browsing, video calls, and streaming, Wi-Fi is more than good enough, and if you have a modern router, Wi-Fi can actually outperform a wired connection in many cases. But a handful of my clients prefer a wired connection: maybe you work from home and want rock-solid reliability, maybe you're transferring large files to a network backup drive, or maybe you're someone who likes the peace of mind of a cable. If that's you, this article is for you.

There's just one catch: if you're using an external ethernet adapter with your Mac, there's a good chance your adapter is actually making things worse.

Why would an ethernet adapter slow things down?

Some ethernet adapters handle the network traffic themselves, leaving your Mac free to do everything else. Others pass that work off to your Mac's processor. When the processor is busy handling network traffic, it can slow down your whole computer, not just your internet connection.

This is why you might have tried plugging in an ethernet adapter expecting a speed boost and ended up with a slower computer than when you started.

How do you know which type you have?

With your ethernet adapter plugged in, you can check using System Report:

1. Click the Apple menu in the top-left corner of your screen

2. Hold the Option key. You'll see "About This Mac" change to "System Information," then click it.

3. In the left sidebar, click Ethernet under the Hardware section

4. Look for a line that says Driver

The one to watch out for is com.apple.DriverKit.AppleUserECM: that means your Mac is doing the heavy lifting instead of the adapter. If you see anything else, you're in good shape. If you don't see an Ethernet section at all, make sure your adapter is plugged in and try looking under the USB section instead.

What should you get instead?

The simplest rule of thumb

If you're shopping for a new adapter or hub, look for anything rated 2.5GbE or faster; those always handle their own processing without taxing your Mac. The spec is usually printed right on the box or in the product name.

Just an ethernet adapter

For a simple USB-C adapter that also works with USB-A (it includes an attached adapter for both), I recommend the Plugable USB-C and USB to 2.5G Ethernet Adapter (MSRP: $24.95). Plug it in and it handles its own work without slowing down your Mac. This is also a great option if you transfer large files to a backup drive or network storage device (NAS) on your network, where the speed difference really adds up.

A faster 10GbE adapter

If you need 10GbE for large file transfers or a fast network storage device (NAS), the StarTech USB4 10GbE Ethernet Adapter is the premium option. It supports 10, 5, 2.5, and 1 Gbps Ethernet and uses a Marvell AQC113 controller that handles network processing without relying on the AppleUserECM driver. I have not personally tested this adapter, so this is a researched recommendation based on the manufacturer's specifications. No separate driver installation is required on a Mac. The StarTech adapter requires macOS 12.4 or newer and a Thunderbolt 3, 4, or 5 or USB4 port. It will not work with a USB 3.1-only USB-C port, including the MacBook Neo and 12-inch MacBook. It costs substantially more than the Plugable and only makes sense if the rest of your network supports speeds above 2.5 Gbps.

A note about monitor ethernet ports

Some monitors, particularly higher-end models, include a built-in ethernet port. These pass the network connection through to your Mac over the same cable that carries video. The same issue applies here. I'm happy to report that my recommended monitor uses the efficient type, so if you're already using that setup you're in good shape.

Key takeaways

• Plug in your ethernet adapter, then open System Report (hold Option and click the Apple menu) to check

• Under the Ethernet section, if you see com.apple.DriverKit.AppleUserECM, replace your adapter

• When shopping for a replacement, look for anything rated 2.5GbE or faster

• Replace it with the Plugable USB-C and USB to 2.5G Ethernet Adapter (MSRP: $24.95) for a simple adapter, or see the 10GbE option above if you need more speed

Further reading

• What's the best WiFi router for your home?

• Time Machine backup drive recommendations

• More product recommendations for Mac and iPhone users

If you're not sure what you're looking at in System Report, or you want help checking your setup, I offer one-on-one tech tutoring sessions in San Francisco and Washington DC, and via Zoom anywhere. Book a session here.