HDMI 21 has been touted as a must-have for new TVs and monitors because its 48 Gbps bandwidth allows for up to 10K resolution and 120 Hz refresh rates for high frame rate gaming Variable refresh rate (VRR) and automatic low-latency mode (ALLM) options are also attractive, especially for Xbox Series X and PS5 owners

But in at least some cases, all of this is a bit of a lie: TFTCentral reports that HDMI 21 is actually an upgrade of HDMI 20 (the more common port version on many TVs and monitors), not but rather a complete replacement of HDMI 20

That doesn't sound like a reason to worry After all, the technology often succeeds and replaces older versions [However, TFTCentral pointed out to the HDMI Licensing Administrator that the HDMI 21 monitors Xiaomi sells do not support HDMI 21 functionality It was expected that this would raise a stink, but in fact it is not a problem at all [The HDMI Licensing Administrator is not upgrading HDMI 21, but allowing HDMI 21 to replace HDMI 21, thereby paving the way for TV and monitor manufacturers to label their screens as HDMI 21 21 compatibility, even if they do not have any of the desired features

"Products can no longer be certified for 21 with 20 alone, and popular features like 4k120, ALLM, and VRR are not mandatory because 21 features are optional to implement," HDMI LA Vice President of Marketing and Operations Brad Bramy told Ars Technica Manufacturers can simply implement eARC, for example, and claim that the device is 21 compliant"

If you're smelling the brown stuff here, we can't blame you The port standard is already complex enough, as we can see from how many different things USB-C can support, but not necessarily do

HDMI is no easier, especially for those who are not tech savvy For example, to get the benefits of HDMI 21 on an Xbox Series X or PS5, you need to make sure you are using the HDMI cable they are shipped with Furthermore, it is possible that devices labeled HDMI 21 may not actually support the full set of standards for connectivity, and we are looking at a thick soup of potential confusion

Currently, manufacturers wishing to use the HDMI 21 standard need to clarify what features the HDMI 21 standard supports, as required by the HDMI Adopter Agreement And the advent of an HDMI 21a standard that supports source-based tone mapping will cause even more headaches But this too will do little to help squash the potential for confusion

So what is the solution? Ideally, in the near future, the rules and requirements for what is called HDMI 21 and USB 32 Gen 2 will be made more stringent by standards bodies

But that may be wishful thinking So our suggestion is to read the fine print of the product you are about to purchase and double-check to make sure you are getting what you expect from an HDMI 21 TV or monitor

At the risk of sounding forward, you may want to consult Tom's Guide, which has a wealth of TV and monitor reviews, including the Best HDMI 21 TVs, Best Gaming TVs, Best Monitors, and Best Gaming Monitors The list includes We also have lists of the best HDMI 21 TVs, gaming TVs, monitors, and gaming monitors

If nothing else, feel free to contact us for our advice and guidance Email the appropriate editor or writer or tweet us @tomsguide