What Is HDMI 2.1?

HDMI 2.1 supports native 10K screen resolution, 4K at 120Hz, 8K at 60Hz, integrated variable refresh rate technology, dynamic HDR. Here's a guide.


In addition to the standard HDMI 2.0 capabilities, HDMI 2.1 adds native support for variable refresh rate technology, dynamic HDR, up to 10K screen resolution, 4K at 120Hz, and many more features.

In December 2017, HDMI Forum revealed the final specifications for HDMI (High-Definition Multimedia Interface) version 2.1.

These include support for higher refresh rates and resolutions, as well as support for many additional features, such as dynamic HDR (High Dynamic Range), eARC (enhanced Audio Return Channel), and VRR (Variable Refresh Rate) technology, among other things.

HDMI 2.1 Supported Resolutions & Refresh Rates

HDMI 2.1 brings support for screen resolutions up to 10K at 120Hz, that’s 10240×4320 pixels! Apart from that, PC and console gamers will get the long-anticipated native 120Hz at 4K support.

For 8K at 60Hz and onwards, you will need new Ultra High-Speed HDMI cables with up to 48Gbps. Both the new cable and HDMI 2.1 standards will be backward compatible with their previous models.

For everything over 8K at 60Hz, HDMI 2.1 will be using DSC (Display Stream Compression), which is an effective form of data rate compression without any impact on the image quality. It increases latency, but the added delay is imperceptible (~1ms).

2.1 hdmi cable

HDMI 2.1 Features

Other features of HDMI 2.1 include the support for dynamic HDR, which implements its metadata with optimal brightness, contrast, color, and other information on a scene-by-scene or frame-by-frame basis.

This provides a more engaging viewing experience, unlike the static HDR, which offers the same metadata for all scenes of the video.

Furthermore, Quick Frame Transport (QFT) and Auto Low Latency Mode ensure responsive gameplay with the low input lag mode (such as Game Mode on many TVs) being automatically enabled when a PC or a console is detected.

With Quick Media Switching (QMS), black screens that take place when toggling between media sources will be shorter, while the enhanced Audio Return Channel (eARC) provides full support, as well as easier control over audio devices and advanced audio formats.

Here’s a list of all the supported features HDMI 2.1 offers in comparison to the previous versions.

what is the latest hdmi standard

What Does This Mean For Gamers?

What’s most interesting for gamers, besides the 4K at 120Hz support, is the native support for variable refresh rate technology (HDMI 2.1 Forum VRR), such as AMD FreeSync and NVIDIA G-SYNC.

VRR synchronizes the display’s refresh rate with GPU’s frame rates for smoother gameplay without screen tearing and stuttering.

LG’s 2019 and newer OLED TVs with HDMI 2.1, for instance, allow the variable refresh rate to be used with both AMD’s and NVIDIA’s compatible graphics cards, as well as the Xbox One and Series S/X consoles.

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Rob Shafer
Rob Shafer

Rob is a software engineer with a Bachelor’s degree from the University of Denver. He now works full-time managing DisplayNinja while coding his own projects on the side.