What is the difference between HDMI 2.0b and HDMI 2.1?

As video and audio standards continue to evolve, HDMI must keep pace with cutting-edge technologies, which is why there are multiple HDMI generations. Represented by version numbers, which started with HDMI 1.0 in 2002, the standard has evolved to HDMI 2.2 in 2026. That said, the two main ports and HDMI cable types you’re likely to encounter are HDMI 2.0b and HDMI 2.1. The first was launched in 2016, while the second hit the market in 2017.

The main difference between HDMI 2.0b and HDMI 2.1 is the amount of bandwidth supported by the ports and cables. HDMI 2.0b guarantees up to 18Gbps, while the 2.1 standard bumps things up to 48Gbps. That’s more than double the data, a feat that translates to better resolution support and improved refresh rates. HDMI 2.0b is limited to 4K/60Hz, which is fine for most movies, shows, and video games. But HDMI 2.1 adds 4K/120Hz support, 8K/60Hz support, and features like variable refresh rate (VRR) and automatic low latency mode (ALLM).

HDMI 2.1 also brought HDMI eARC into the mainstream. For those who don’t know, “ARC” stands for Audio Return Channel, an HDMI feature that allows devices to send audio data downstream and upstream over a single cable. eARC (the “e” stands for enhanced) ensures that any device or media connected to your TV, including built-in apps, routes audio through the same HDMI connection to a soundbar or AV receiver.

While one HDMI generation becomes ancestral to another, the good news is that all versions are backwards compatible. This means you can plug an HDMI 2.1 cable into a 2.0 port; you’ll simply receive the best video and audio a 2.0 connection offers (up to 4K/60 Hz). Fortunately, HDMI 2.0 is usually more than sufficient if you only care about watching 4K movies and shows. Cinematic and episodic content are often limited to 24fps, so 4K/60Hz is more than enough for most TVs and projectors.

When should you really worry about investing in HDMI 2.1 hardware and accessories? If you’re a dedicated PC gamer with a high-end rig or you own a current-gen console, like a PlayStation 5 or Xbox Series X. The best gaming PCs support refresh rates of 144Hz or higher, as well as optimization features like AMD FreeSync Premium Pro. If you own this type of equipment or want to get into gaming, you need to make sure that all your equipment supports HDMI 2.1 or higher. High-end gaming displays may even include DisplayPort connections, which may be better than HDMI (depending on the device you’re using and the DisplayPort and HDMI standards it supports).