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Key Features

  • 27" FHD (1920x1080) TN Display
  • AMD FreeSync™ Technology
  • Dynamic Action Sync
  • Black Stabilizer
  • On Screen Control
  • Smart Energy Saving

available sizes:

Suggested Price


Suggested Price
Promotion Price*


Promotion Price*
27MK400H-B Full HD Display

Full HD Display

You’re in front of your monitor for hours on end. Make the most of your time, with an LG Full HD LED monitor. The clarity of 1080p pixel resolution is a game-changer. Simply put, everything looks more detailed than standard HD.

AMD FreeSync

AMD FreeSync™

With FreeSync*, gamers can experience seamless, fluid movement throughout hi-res, fast-paced games. FreeSync virtually eliminates screen tearing and stuttering.

*FreeSync is only available when it is connected to Display Port or HDMI.

Dynamic Action Sync

Dynamic Action Sync

Minimize input lag with Dynamic Action Sync so you can catch every single moment in real-time.

27MK400H-B Black Stabilizer

Black Stabilizer

Keep visibility even in dark scenes. LG's Black Stabilizer senses dark scenes and helps make it brighter so that you can find the enemies hiding and waiting to attack your player in the dark.

On-Screen Control

On-Screen Control

On-Screen Control puts a host of essential monitor settings into a handy window for quick, easy access. Volume, brightness, picture mode presets, Screen Split 2.0 and Dual Controller and more can now be adjusted with just a few clicks of the mouse, instead of hard buttons on the monitor.

Learn More


Watch how the On-Screen Control feature can help configure your display for maximum organization and efficiency.

On-Screen Control

Software download required to enable OnScreen Control. For download details, visit

F6 22MK430H_2018_Feature_06_WallMount_D

Wall Mountable

This monitor gives you the freedom to take it off the desk and hang it on the wall. Liberate your viewing options and save desktop space with this wall-mountable LG monitor.

Mounting hardware not included.

ENERGY STAR® Qualified


ENERGY STAR® certified monitors meet stringent energy efficiency requirements set by the US Environmental Protection Agency in On, Sleep, and Off Modes. On average, monitors that have earned the ENERGY STAR® are 25% more energy efficient than standard options.

Cabinet / Accessories

What People Are Saying

Rated 4 out of 5 by from Good monitor for the price Good monitor for the price at $102 But it dosnt have have USB port nor built in speaker
Date published: 2019-05-16
Rated 4 out of 5 by from Quality screen output Good clarity of images, simple to setup and great price
Date published: 2019-05-15
Rated 5 out of 5 by from Great Monitor - Sharp Image Very Happy with this Monitor bought it from Costco. I was looking for a new monitor with anti glare features and this fit the bill. It has amazing color, sharpness and picture quality. Definitely a upgrade I needed from my old monitor. Along with great design it comes at a reasonable price. Has tilt feature and you can adjust colors with software provided right on the screen.
Date published: 2019-02-25
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Ask your questions. Share your answers.
Please first review the detailed product information and help guides in the Product Support section for this product prior to posting a question.

Does the LG 24MK400H-B 24" Class Full HD Monitor have built-in speaker?

Asked by: Rehne
Hello, the 24MK400H-B does not have built-in speakers. ^AC
Answered by: Amber C
Date published: 2018-12-12

Which LG monitors are compatible with a Mac (Mac Mini) computer?

Asked by: ABQGreg
Most, if not all of our monitors are Plug and Play monitors so they all will work with a Mac Mini. It's just a matter of connectivity and depending on what connections you have on your mac mini, you may or may not need adapters to make the necessary connections depending on what connectivity the monitor has...^IFV
Answered by: LGJoel
Date published: 2018-12-10

Can this monitor be use as a computer monitor and cable TV?

Asked by: Dking174
The main difference between a monitor and a TV is that monitors do not have built-in tuners like TVs do and only a few monitors have built-in speakers. To use the LG 27" Class Full HD TN Monitor with AMD FreeSync (27" Diagonal), Model # 27MK400H to watch cable programming, your cable's Set-Top box will need to have an HDMI Out which you can connect to the HDMI In on the monitor and you will need to connect a pair of active or passive computer speakers to the monitor for sound since it doesn't have built-in speakers...^IFV
Answered by: LGJoel
Date published: 2018-10-17

I have two camera systems, so can i input both a HDMI and dsub at the same time to this monitor? Can i split screen the two systems on the one monitor display at the same time?

Asked by: justin113
The HDMI port on the LG 27" Class Full HD TN Monitor with AMD FreeSync (27" Diagonal), Model # 27MK400H is a digital port while the D-Sub port on it is an analog port so the two ports are independent on one another. You cannot view two inputs simultaneously on this monitor, it does not support Picture-by-Picture. You can download the OnScreen software which has Screen Split 2.0 that enables you to resize and display multiple windows at once, with 14 options including four different picture-in-picture (PIP) choices...^IFV
Answered by: LGJoel
Date published: 2018-06-19
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