Now called HDMI 2.1b following minor updates, the spec’s arrival brought new capabilities, starting with higher video resolutions and refresh rates. It supports 4K video at 120 Hz (higher with certain PC graphics cards), 8K video at 60 Hz, and even 10K video. HDMI 2.1b’s speedy refresh rates mostly come into play with gaming, where it facilitates other advanced features like VRR (variable refresh rate) for more fluid gameplay as well as ALLM (auto low-latency mode) and QFT (quick frame transport) for reduced latency. The spec also supports all high-bitrate audio formats, including DTS Master Audio, DTS:X, Dolby TrueHD, and Dolby Atmos.
Other notable features announced with HDMI 2.1 include HDMI eARC for lossless hi-res audio transmission between eARC-supported devices, and dynamic HDR support, which allows for HDR content to be optimized for video scene-by-scene or even frame-by-frame.
Photograph: Silkland
Before you worry too much about which port you’re using, there are some important caveats to note. Dolby Vision HDR delivered dynamic HDR to compatible TVs over HDMI 2.0 years before HDMI 2.1, due to how its dynamic metadata is embedded in the video, and its rival, HDR10+, can do the same. Similarly, HDMI eARC is available over HDMI 2.0, as shown in newer TVs from brands like TCL and Hisense, providing two HDMI 2.1 inputs and a separate HDMI eARC port.
HDMI 2.1 is backward-compatible with older HDMI versions, but not all features will be supported. You may also need to upgrade your HDMI cables for the higher bandwidth required, swapping out high-definition cables for ultra-high-definition cables like this one.
What’s New in HDMI 2.2?
With support for 8K and even 10K video (which essentially doesn’t exist for consumers) and all major hi-res audio formats, HDMI 2.1b has your home theater covered for the foreseeable future. That means you don’t have to worry about upgrading your TV or audio devices for HDMI 2.2 anytime soon.
Instead, the HDMI Forum is pitching the new spec for commercial applications and advanced consumer tech like augmented reality (AR) and virtual reality (VR) devices. HDMI 2.2 once again upgrades the bandwidth transmission rate, this time doubling it from 48 Gbps to 96 Gbps to improve “demanding data-intensive, immersive and virtual applications …” according to the Forum.