What is the maximum length for hdmi cable?

Question

Hi,

What is the maximum length of hdmi cable that can be used without any signal loss

Answer 1

I like the answers by 'He who must hold the remote'. They are usually very correct.

However there's a small addition needed here. HDMI being a very high frequency signal moves on the 'surface' of wire and so practically the AWG of wire doesn't matter to that extent as with the speaker wires for example. On very very long runs it does have a role to play though very small.

Answer 2

The issue is signal degradation and that starts as soon as the signal starts to travel down a wire.

A better question is therefore how long an HDMI cable can be and still give a useable signal. There isn't one specific maximum because useful length is really a function of the signal you want to connect (higher resolution / lower length).

But ... Bluejean Cables sell a cable that their website claims they have used to " run 1080p/60 video 125 feet without degradation" ... although they only sell (Link 1) it at lengths up to 100 ft ($256). This site has an excellent information centre (Link 2) that goes in some depth into the issues with HDMI.

Using signal boosters or baluns and Cat 5 cable can extend the HDMI signal to upward of 500ft (at lower resolution) ... but this is no longer, strictly speaking, a "simple" HDMI cable (See 3rd link for a number of options).

Answer 3

Depends.

The High-Definition Multimedia Interface (HDMI) is a licensable audio/video connector interface for transmitting uncompressed, encrypted digital streams, audio and video.

The HDMI specification does not define a maximum cable length. As with all cables, signal attenuation becomes higher at longer lengths. Because the digital datastream is less susceptible to interference than its analog equivalent, the picture quality is 100% similar on properly functioning cables, regardless of length. The tolerances for HDMI cables are incredibly tight. Because a digital signal is comprised of 1s and 0s, sent over four channels with 19 pins inside the cable, and because these 1s and 0s need to start and end at the exact same time, the manufacturing tolerances for cables are very high.  It's for that reason that cables must be tested at an HDMI Authorized Testing Center before they can be marked with the HDMI logo.Unlike analog, there is no such thing as an HDMI cable that makes the digital audio or video data come out better than another. If the 1s and 0s make it to the other end, the cable has done its job, period.  In addition, some HDTVs are designed with HDMI electronics that have greater sensitivity and active equalizer technology to accommodate longer cable runs.

50ft HDMI cables from ceiling projectors projectors are common and the link below actually sells 100ft with guarantee. For very long cabling needs, there are cable extender products that effectively boost the signal and extend the effective cable length.

Answer 4

It's not signal loss, it's cross-talk inside the cable that is the problem.

Generally you can use generic/cheap HDMI cables for up to about 15 ft.  

But over longer runs, the signals traveling on all those tightly bundled wires inside the cable start to interfere with each other.  Using slightly thicker wires with thicker wire-to-wire insulation seems to solve the problem.

So either buy the BlueJeans cables or the cables from MonoPrice with the lower AWG number (Lower number = thicker wire).