While many of us connect to Wi-Fi to browse the web, most Wi-Fi routers require a hard-wired Ethernet connection to connect you to the internet. But how long does it take for an Ethernet cable to fail?

How long can an Ethernet cable be?

Ethernet cables can be any length, but at a certain point, the distance the signal needs to travel becomes a little too long. Even if a signal can travel great distances, the time it takes to get from A to B can become so long that end users end up with very slow connection speeds.

So, how long does an Ethernet cable last before losing signal?

Generally speaking, standard Ethernet cable (the twisted-pair Ethernet cable most people are familiar with) can be up to 328 feet (100 meters) long before speeds are affected. This is the case for cables at room (or ambient) temperature, which generally refers to most residential environments. Businesses, offices, and industries are likely to use longer Ethernet cables.

This is because longer cables make it more difficult to transmit signals due to increased resistance. Resistance is a phenomenon in electronic circuits in which the circuit material resists the flow of electricity. In Ethernet cables, copper wires act as electrical conductors. As the length of the wire increases, the resistance increases.

As resistance increases, the speed of the electrical signal begins to decrease. This is where connection strength, latency, and bandwidth can be affected. The further a signal travels, the lower the bandwidth and speed, and the longer the latency.

However, this maximum value can vary significantly depending on the type of Ethernet cable in question. So let's discuss the different maximum lengths for different Ethernet types.

Ethernet cable length

There are three main types of Ethernet cables:

• optical fiber
• Coaxial
• twisted pair

These cables differ in material composition and wiring construction. Coaxial and twisted pair cables use copper wire, and fiber optic cables use very thin glass fibers.

Fiber optic cables transmit data in the form of light, increasing connection speeds. There are several reasons why fiber optic cables are better than copper cables, increased speed being just one of them.

Because of this key difference, fiber optic cables have different maximum lengths than coaxial and twisted pair cables. According to the Router Switch blog, fiber optic cables can extend up to 2,000 meters (or 6,581 feet) in 10Mbps and 100Mbps internet.

On the other hand, according to Cisco Press, the maximum distance of coaxial cable can reach 500 meters. Meanwhile, Cisco Press also says that twisted-pair cable can only go up to 100 meters (328 feet).

Does the creation of Ethernet cables affect signal strength?

Answering this question is a bit tricky. The answer is "yes, with a but."

I mean, yes, the type of ethernet cable produced does affect signal strength, but it's unlikely that most normal people will encounter a situation where calculating the resistance of a specific ethernet cable becomes an issue. According to the official ANSI/TIA/EIA 568-B [PDF] guideline, the maximum allowable cable length for twisted pair Ethernet cable is 90 meters, with 5 meters on each end for wiring.

So, in short, the longer the Ethernet cable, the more likely you are to encounter data transfer issues. These guides cover Cat5, Cat5e, Cat6, Cat6a, and more—in fact, every Ethernet cable you might use.

It's worth noting that fiber optic cables do not fall into these categories. Instead, they are in a league of their own and can reach greater distances thanks to their fiberglass interior. Additionally, coaxial cable is not included in the Cat classification system.

Keep Ethernet Cable Length in Mind

If you want to purchase an especially long Ethernet cable, be sure to be aware of the effect that added length will have on signal strength. If you want a long cable without sacrificing speed, consider using fiber optic or twisted pair coaxial cable.