About the LG UltraFine 4K Display
The 21.5-inch LG UltraFine 4K Display features a 4096 x 2304 resolution, a P3 color gamut, 500 cd/m2 of brightness and built-in stereo speakers. Integration with macOS lets you control your display's volume and brightness without the need for physical buttons on the display.
When you connect the display using a single USB-C cable (included), it provides up to 60W of charging power to your MacBook, MacBook Air, or 13-inch MacBook Pro. The display has three downstream USB-C ports (480 Mbps) that offer additional connectivity and power to compatible devices and accessories.
System requirements and compatible Mac models
The LG UltraFine 4K Display requires a Mac with one or more USB-C ports, running macOS Sierra 10.12.1 or later (macOS Sierra 10.12.2 or later is recommended).
You can use the LG UltraFine 4K Display with these Mac models:
4096 x 2304 @ 60Hz
- iMac Pro introduced in 2017
Learn how to connect multiple displays to your iMac Pro
- iMac introduced in 2017 or later
- Mac mini introduced in 2018
Learn how to connect multiple displays to your Mac mini (2018)
- MacBook Pro introduced in 2016 or later
- MacBook Air introduced in 2018
- MacBook introduced in 2016 or later
4096 x 2304 @ 48Hz
- MacBook introduced in 2015
A Mac with built-in USB-C or Thunderbolt 3 (USB-C) ports is required; the display isn't compatible with Mac models that use Thunderbolt 2.
Learn how to adjust your display’s resolution.
USB-C power delivery
The LG UltraFine 4K Display provides up to 60W of power over USB-C and can fully power these Mac models using the included USB-C cable:
- 13-inch MacBook Pro models introduced in 2016 or later
- MacBook Air introduced in 2018
- MacBook introduced in 2015 or later
The UltraFine 4K won't fully power 15-inch MacBook Pro models because they require 85W. If you try to power your 15-inch MacBook Pro through the display, your notebook's battery will be used during times of heavy activity. To fully power your 15-inch MacBook Pro and charge its battery, connect it to its Apple 87W USB-C power adapter when you use it with the UltraFine 4K.
The LG UltraFine 4K Display provides 7.5W to each of its three downstream USB-C (480 Mbps) ports. To charge Apple Lightning-based devices and accessories — such as iPhone, iPad, AirPods, Magic Keyboard, Magic Trackpad 2, and Magic Mouse 2 — you can use the Apple USB-C to Lightning Cable or a combination of the Apple USB-C to USB Adapter and the Apple Lightning to USB Cable.
If you have issues connecting the display
- If you don't see an image after connecting the LG UltraFine 4K Display to your Mac, make sure that you're using the cable that came with the display. If you don't have it, you can use a USB-C 3.1 cable that supports the USB 3.1 Gen 1 specification. Learn more about USB on Mac computers.
- Get help with video issues if you still don't see an image when using the correct cable.
- If the LG UltraFine 4K Display doesn't power on or you don't see an image after following the steps in the article above, contact LG to get service for your display.
- You can download the LG UltraFine 4K Display owner's manual and LG Screen Manager software on the LG support page. Firmware updates for the LG UltraFine display are managed using LG Screen Manager. Run it periodically to check for and install firmware updates.