The numbers that matter
HDMI versions define how much data the cable can carry, which sets the ceiling on resolution and refresh rate.
When HDMI 2.0 is enough
If your display tops out at 4K 60Hz - which is most TVs and monitors sold in Australia - an HDMI 2.0 cable is all you need. Streaming, Blu-ray, standard console gaming at 4K 60fps: HDMI 2.0 handles it without issue.
When you need HDMI 2.1
Gaming at 4K 120Hz or 144Hz requires HDMI 2.1 - both the cable and the ports on the display and source must be 2.1. The PS5 and Xbox Series X both output over HDMI 2.1. PC graphics cards with HDMI 2.1 output have been standard since the RTX 3000 and RX 6000 series. If you have an 8K display, HDMI 2.1 is the only option.
Active vs passive and cable length
Passive HDMI cables carry the signal well at short runs. For HDMI 2.1 at lengths above 3m, signal loss starts to become a factor: stick to cables under 3m for full-bandwidth 2.1, or use an active cable at longer lengths. The Cable Finder flags when a run needs an active cable and restricts results to active options automatically.
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