What HDMI Cable Do I Need?

Understanding HDMI Cables: A Plain-English Guide

HDMI cables are one of the most over-complicated, over-marketed products in home electronics. The truth is simple: HDMI is a digital connection. The signal either arrives perfectly or it doesn't arrive at all. There's no such thing as a "better picture" from a more expensive cable — as long as the cable meets the spec your devices need, a $8 cable from Monoprice is identical to a $120 cable from a premium brand.

HDMI 2.0 vs HDMI 2.1: What's the Difference?

HDMI 2.0 (also called "High Speed") supports up to 4K at 60Hz with 18 Gbps of bandwidth. This is more than enough for streaming 4K content from Netflix, watching Blu-rays, cable TV, and casual gaming. The vast majority of people only need HDMI 2.0 cables.

HDMI 2.1 (also called "Ultra High Speed") bumps the bandwidth to 48 Gbps, enabling 4K at 120Hz, 8K at 60Hz, and features like eARC, VRR (Variable Refresh Rate), and ALLM (Auto Low Latency Mode). You only need HDMI 2.1 if you have a PS5, Xbox Series X, or high-end gaming PC and want to take advantage of 4K at 120fps — or if you need eARC for lossless Dolby Atmos audio.

What About eARC?

eARC (Enhanced Audio Return Channel) is a feature of HDMI 2.1 that lets your TV send full-quality, uncompressed surround sound — including Dolby Atmos and DTS:X — back to a soundbar or AV receiver through a single HDMI cable. The older ARC (available on HDMI 2.0) can only send compressed audio, which means you lose quality with advanced surround formats.

If you use your TV's built-in streaming apps (like the Netflix or Disney+ app on your Samsung or LG TV) and route the audio to an external sound system, eARC is how you get the full Dolby Atmos experience. Without it, your TV will downmix the audio to a compressed format before sending it to your soundbar.

Cable Length: When It Matters

For short runs (under 10 feet), any certified HDMI cable will work perfectly. The challenge comes with longer runs. HDMI signals degrade over distance because they're high-bandwidth electrical signals traveling through copper wire. For HDMI 2.0, passive copper cables work reliably up to about 15–20 feet. For HDMI 2.1's higher bandwidth, passive cables start struggling around 10–15 feet.

For longer runs, active HDMI cables have a small chip inside that boosts the signal. For runs over 25 feet, fiber optic HDMI cables are the gold standard — they convert the electrical signal to light, transmit it with zero degradation, and convert it back at the other end. They're more expensive but are the only reliable option for long distances.

Need to calculate the exact cable length for an in-wall installation? Use our HDMI Cable Length Calculator to measure the path including bends, drops through walls, and routing behind furniture.