Have you ever wondered how long a single USB cable can go? How about what their extended max length is? We're here to answer these questions!
USB cables all have a maximum length, but that max length varies based on the version of the USB cable. You can also extend a cable to go beyond that limitation. We will go over this in detail in this article.
There are many different types of USB cables, each with its limits.
In the table below, you can see the recommended cable length for getting the maximum speeds and available power for each type of USB cable. These are the recommended lengths without using any USB extensions or active cables.
|Mode Name||Recommended Cable Length||Bandwidth|
|USB 1.1 (Full Speed)||3 m (9 ft)||12 Mbps|
|USB 2.0 (High Speed)||5 m (16 ft)||480 Mbps|
|USB 3.2 Gen 1||2–3 m (6–9 ft)||5 Gbps|
|USB 3.2 Gen 2||3 m (9 ft)||10 Gbps|
|USB 3.2 Gen 2x2 (USB-C)||3 m (9 ft)||20 Gbps|
|USB4 (USB-C)||0.8 m (31 in)||40 Gbps|
If properly extended, you can use a longer USB cable with one of the USB extension methods described below. The USB device can lose signal strength or quality if the cable is longer than the recommended length. Not correctly extending it can cause packet loss, which will result in a lower speed (due to a lower throughput).
USB cables that support higher speeds, like USB4's USB-C type 2.1 cable, require a shorter length.
With an increased transfer rate, such as those supported by USB 3.x and USB4, the USB communication becomes more susceptible to interference as the cable length increases.
USB cables were initially made for short-range transfer between a computer and other devices. Nowadays, there are more uses for USB cables, so the limitations are more noticeable. There are ways to get around this limitation with USB extensions, though.
USB cables are made of copper, limiting the cable's length because it loses signal strength the farther it reaches. This signal loss (attenuation) is measured in decibels per distance—the greater the distance, the more signal loss. The more loss it has, the higher chance that the receiver can't detect the signal or read it correctly. This signal degradation can be reduced with lower gauge (thicker) wiring in the USB cable.
Signal degradation can also be reduced by using better insulation in the cable. Since copper wires are affected by noise or interference, a lack of proper insulation can affect the quality of the signal.
If you want to extend your USB cable beyond the limitations, there are a few ways of doing so. You can use a better quality cable, active cable, or different types of extenders. Below, we explain what each of these is to find the best solution for your situation.
Better Quality Passive USB Cable
Passive cables, in general, provide no extension to the max length that USB cables can reach at their maximum speeds. However, a better quality passive cable made of lower gauge (thicker) copper with better cable shielding will allow you to have less signal loss when going past the recommended lengths. This will allow you to get the maximum speeds within the recommended cable lengths and improved speeds past the recommended lengths.
Active USB Cable
Active USB cables allow data to be transferred at a greater distance due to circuitry on one or both ends of the cable. This circuitry boosts and repeats the signal so that it can reach a further distance. Active USB cables can sometimes come with external power adapters to boost the signal properly.
Find USB 3.0 active cables on Amazon (affiliate link).
Powered USB Hub
A powered USB hub will act the same as an active USB cable by repeating any received signals. Each hub can extend the USB cable by the recommended length. Powered USB hubs need to be powered via an AC adapter.
You can use multiple hubs to extend the connection even farther, but you can only use up to 5 hubs total on one connection. After that, the connection may become unstable and unreliable.
Multiple extensions may result in higher latency, which is the communication delay between the USB host and the USB device. Extended USB runs may result in undesirable lag for some use cases such as video or audio.
Find USB 3.0 powered hubs on Amazon (affiliate link).
USB Over Ethernet Extension Adapter
A USB over Ethernet extension adapter is a hub with a USB port (or multiple ports) and an Ethernet port. The hub converts the USB signal to transmit through an Ethernet cable, then converts it back to USB on the other side with another hub.
USB over Ethernet extension adapters can reach speeds of up to 1000 Mbps while using a USB 3.0+ device and cable along with a Cat 5e or higher cable.
Note that a USB over Ethernet extension adapter is not the same as a USB network adapter, allowing Ethernet network connection via a USB port.
Find USB 3.0 Ethernet Adapters on Amazon (affiliate link).
USB Over Fiber Extension Adapter
A USB over fiber extension adapter is an adapter with a USB port and a fiber-optic port. The hub converts the USB signal to transmit through a fiber-optic cable, then converts it back to USB on the other side with another adapter.
USB over fiber extension adapters can reach speeds of 5 to 10 Gbps while using a USB 3.0+ device and cable along with a fiber-optic cable.
Learn more in my article USB Over Fiber?! Extend USB beyond its limits.Transwan USB 3.0 Fiber Extender Check Price on Amazon (affiliate link)
Find a USB 3.0 Fiber Extender on Amazon (affiliate link).