Long HDMI cables can be useful in a number of situations, from setting up a home theater to connecting digital signage. But is there a limit to the length of the HDMI cable? Here is everything you need to know.
Why does HDMI cable length matter?
High-Definition Multimedia Interface, or HDMI, is the most common display interface today. It is used in everything from televisions to monitors to electronic art. By using a single HDMI cable, you can transmit audio and video signals from one device to another.
You will find HDMI cables in various sizes on the market. Some are about a foot long, while others are several meters long. But if you’re curious about the maximum length of an HDMI cable, there’s no such thing. The official standard HDMI specification does not recommend a cable length. As long as an HDMI cable meets performance standards and can properly carry the signal from one end to the other, it can be any size.
However, HDMI cables, like anything else, must obey the laws of physics. So any digital signal traveling through an HDMI cable encounters resistance. The level of resistance depends on several factors, the most important being the material of the cable’s conductor and its gauge.
As a result, depending on its conductor and gauge, an HDMI cable can only go so far before the signal begins to degrade, causing artifacts in the video or audio output. However, a reputable brand will not make cables long enough to create such problems.
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Maximum length of an HDMI cable
As mentioned, the HDMI specification does not indicate the length of the cable. But the HDMI Licensing Administrator, an organization responsible for promoting and licensing HDMI technology, notes that early tests in the Ultra High Speed (UHS) cable program suggest that passive UHS HDMI cables can be up to five meters. A passive HDMI cable is your standard HDMI cable, featuring HDMI ports on each end connected by shielded copper wiring.
For the uninitiated, UHS cable is the latest and only type of HDMI cable that meets the requirements to ensure full compatibility with every feature of HDMI 2.1a. So if you’re looking to buy an HDMI cable today and want to be prepared for the future, a UHS HDMI cable is the way to go.
Older generation passive HDMI cables, such as Standard HDMI (HDMI 1.0/1.1/1.2) and High Speed HDMI (HDMI 1.3/1.4), can be as long as 49 feet, while relatively newer premium High Speed HDMI cables cables (HDMI 2.0) are mostly limited to 25 feet.
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Active and Optical HDMI Cables
Active and optical HDMI cables can reach longer lengths than passive HDMI cables. Active cables can do this because they use electronic circuitry to boost the signal and compensate for any signal degradation.
Active HDMI cable
Cable Matters Active UHS HDMI Cable
Use this Powered HDMI 2.1 cable from Cable Matters to go up to 25 feet without signal loss, complete with a port for external power if your source device can’t keep up.
Optical cables, on the other hand, use light instead of electricity to move the signal from one end to the other. The light-based signal is less prone to degradation than an electrical signal traveling through copper wires. However, an optical cable is usually more expensive compared to its active cable counterparts.
optical hdmi cable
Depending on the generation of HDMI, the length of an active or optical HDMI cable can range from a few dozen to 100 feet. If you need even more length than a single active or optical HDMI cable can provide, you’ll need to use HDMI cable extenders.
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Lots of options for a long HDMI cable
As you can see, the maximum length of an HDMI cable is not as straightforward as you might expect. Fortunately, between passive, active, and optical HDMI cables, you’ll likely find a suitable cable to meet your needs. And if you need something even longer, you can always use an extender.
That said, stick with the big name brands when shopping for an HDMI cable and look for official certification for the best quality cables. For example, both premium High Speed and Ultra High Speed HDMI cables are certified by the HDMI license manager. Certification will ensure that the cable meets the requirements to support the features offered by its HDMI generation.