HDMI version numbers appear everywhere in product specifications, yet many consumers struggle to understand what these numbers actually mean for their viewing experience. The difference between HDMI 1.4, 2.0, and 2.1 determines what resolutions, refresh rates, and features your equipment can support. This guide breaks down each major HDMI version, explaining their capabilities and helping you determine which version you actually need.
How HDMI Versions Work
Before comparing versions, it's important to understand what HDMI versions represent. An HDMI version defines a specification, essentially a set of rules about what signals and features HDMI equipment can support. When a device has an HDMI 2.1 port, it means that port meets the HDMI 2.1 specification requirements.
Each new HDMI version builds on previous versions, adding higher bandwidth capacity and new features while maintaining backwards compatibility. An HDMI 2.1 device works perfectly with HDMI 2.0 or 1.4 equipment, though it operates at the capabilities of the lower-spec device.
Cables don't technically have HDMI version numbers. Instead, cables are rated by speed, such as "High Speed" or "Ultra High Speed." However, Ultra High Speed cables are required for full HDMI 2.1 capabilities. Marketing often uses version numbers for cables, which can be misleading.
HDMI 1.4: The Foundation
Released in 2009, HDMI 1.4 introduced several features that became standard for modern home entertainment. While superseded by newer versions, many older devices still use HDMI 1.4, and understanding its limitations helps when integrating older equipment.
Resolution and Refresh Rate
HDMI 1.4 supports 4K resolution, but only at 30Hz. This means 4K content plays at 30 frames per second, which is adequate for video but creates noticeable input lag for gaming and lacks the smoothness of higher refresh rates. At 1080p, HDMI 1.4 supports up to 60Hz, which was the standard for HD gaming and video at the time.
Key Features Introduced
HDMI 1.4 introduced the Audio Return Channel, allowing your TV to send audio back to a connected soundbar or receiver without a separate optical or analogue audio cable. It also added support for 3D video, which was popular briefly but has largely fallen out of favour.
The HDMI Ethernet Channel was another 1.4 addition, allowing network data transmission through HDMI cables. However, this feature never saw widespread adoption and remains rarely used.
HDMI 2.0: The 4K Standard
Arriving in 2013 with subsequent updates through 2016 (2.0a and 2.0b), HDMI 2.0 became the workhorse of the 4K era. Most 4K televisions, Blu-ray players, and streaming devices from the mid-2010s through early 2020s use HDMI 2.0.
Resolution and Refresh Rate
HDMI 2.0 doubled the bandwidth to 18Gbps, enabling 4K at 60Hz. This is the standard for current 4K streaming and Blu-ray content. At this resolution and refresh rate, video plays smoothly and gaming feels responsive, though competitive gamers would later demand even higher refresh rates.
HDR Support
HDMI 2.0a added support for HDR10, the foundational HDR format used by streaming services, UHD Blu-rays, and most gaming content. HDMI 2.0b extended this with support for Hybrid Log-Gamma, a broadcast-oriented HDR format. If your 4K TV and content support HDR, you're likely using these HDMI 2.0 variants.
Audio Improvements
HDMI 2.0 expanded audio support to 32 audio channels, up from 8 in previous versions. It also supports higher audio sampling rates. These capabilities enable object-based audio formats, though full uncompressed Dolby Atmos requires the later eARC feature.
For most users, HDMI 2.0 remains perfectly adequate. If you're streaming 4K content, watching UHD Blu-rays, or gaming at 4K 60Hz, HDMI 2.0 handles everything you need. Only specific use cases like 4K 120Hz gaming require upgrading to HDMI 2.1.
HDMI 2.1: The Current Standard
Released in 2017 with widespread adoption beginning around 2020, HDMI 2.1 represents a major leap in capability. The PlayStation 5, Xbox Series X, and latest graphics cards take advantage of HDMI 2.1 features, as do premium televisions from all major manufacturers.
Massive Bandwidth Increase
HDMI 2.1 supports up to 48Gbps bandwidth, nearly triple that of HDMI 2.0. This enables 8K video at 60Hz and 4K at an impressive 120Hz. For gamers, 4K 120Hz means games can run at high resolution with the responsiveness previously only available at lower resolutions.
Variable Refresh Rate (VRR)
VRR dynamically adjusts the display's refresh rate to match the source content's frame rate. When a game's output fluctuates between, say, 45 and 90 frames per second, VRR ensures each frame displays at the right time, eliminating screen tearing and stuttering. This feature transforms the gaming experience, particularly in demanding games with variable performance.
Auto Low Latency Mode (ALLM)
ALLM automatically enables game mode on your display when it detects gaming content. This ensures minimal input lag during games while allowing post-processing for movies and TV shows. The automation eliminates the need to manually switch display modes.
Enhanced Audio Return Channel (eARC)
eARC dramatically increases audio bandwidth over the original ARC, supporting lossless audio formats like Dolby TrueHD, DTS-HD Master Audio, and uncompressed Dolby Atmos. For home theatre enthusiasts, eARC enables the highest audio quality from television apps without requiring source devices connected to an AV receiver.
Quick Frame Transport and Quick Media Switching
These features reduce latency and eliminate the blackout when switching between content with different refresh rates. They contribute to a smoother overall user experience, particularly when navigating between games, streaming apps, and other content.
Which Version Do You Need?
Your equipment and usage patterns determine the HDMI version you require.
For Basic Streaming and TV Watching
HDMI 2.0 handles all current streaming content beautifully. Unless you're planning to watch 8K content, which remains rare, you won't notice any difference with HDMI 2.1 for passive viewing. Even HDR streaming works perfectly through HDMI 2.0.
For Casual Gaming
If you play games primarily for story and atmosphere rather than competitive edge, HDMI 2.0 and 4K 60Hz provide an excellent experience. Many console games are designed around 60Hz, and the difference between 60Hz and 120Hz is less noticeable in single-player adventures than in fast-paced multiplayer games.
For Competitive Gaming
Serious gamers, particularly those playing competitive shooters or fast-paced games, benefit significantly from HDMI 2.1. The combination of 4K 120Hz, VRR, and ALLM delivers noticeably smoother, more responsive gameplay. If you own a PS5, Xbox Series X, or gaming PC with a recent graphics card, HDMI 2.1 unlocks these devices' full potential.
For Home Theatre Enthusiasts
If you have a Dolby Atmos speaker setup and want lossless audio from streaming apps, eARC through HDMI 2.1 is essential. For Blu-ray playback where the player connects directly to an AV receiver, HDMI 2.0 typically suffices for audio, but 2.1 futureproofs your installation.
Don't upgrade equipment solely for a higher HDMI version number. Evaluate your actual needs. HDMI 2.0 remains capable for most users. Upgrade to HDMI 2.1 when specific features like VRR or eARC will meaningfully improve your experience, not just for the specification number.
Future HDMI Development
HDMI development continues, with the HDMI Forum periodically updating specifications. The current HDMI 2.1a adds Source-Based Tone Mapping for improved HDR handling. Future updates will likely increase bandwidth further for 10K resolution and beyond, though such content remains years away from mainstream availability.
When purchasing new equipment, choosing HDMI 2.1 compatible devices provides the best future-proofing. Even if you don't use all features immediately, you'll be ready as content and additional devices catch up to the specification's capabilities.