USB 3.0 vs 3.1 - What's the difference?

The universal serial bus, or USB, has been a stalwart connector for all sorts of devices and systems for almost two and a half decades. It's consistently kept pace with new demands for speed and features, and today is one of the most comprehensive connectors out there. That does depend on which version of USB you make use of, though, with older generations not offering the same capabilities as the latest. In a head to head of two capable connectors like USB 3.0 vs 3.1, USB 3.1 almost always comes out on top.

The difference between USB 3.0 and 3.1 isn't drastic, but it can make a big difference depending on the devices you own and what you want to do with them. Here's how USB 3.1 vs USB 3.0 fare against one another.

Naming confusion
Before addressing the main USB 3.0 vs 3.1 debate, it's important to clear up what's being discussed. The organization that promotes and supports USB development, the USB Implementers Forum, retroactively renamed all third-generation USB connections at the release of USB 3.2.

Technically, USB 3.0, 3.1, and 3.2, are now all known as USB 3.2. To avoid confusion, manufacturers describe their USB products in terms of speed: SuperSpeed USB 5 Gbps, SuperSpeed USB 10 Gbps, or SuperSpeed USB 20 Gbps, depending on the USB version they support. Bear that in mind when buying USB compatible devices.

JMTO takes this naming convention in mind, and where necessary, uses both the traditional USB namings and labels cables with the maximum speeds they can handle. That said, it's important to note that when it comes to third-generation USB cables, they are fully compatible with themselves and USB 2.0 ports.

That changed a little with USB 3.2 and will change again with USB4 (see below).

The difference between USB 3.0 and 3.1

The core difference between USB 3.0 and 3.1 is transfer speed. When it was introduced in 2008, USB 3.0 revolutionized USB bandwidth. USB 3.0 increased the maximum transfer speed to 5Gbps – working out to around 500MB/s in the real world – using its new SuperSpeed transfer mode, a near 10 fold increase over its predecessor, USB 2.0.

To differentiate this higher speed connector over older USB ports and devices, cables were equipped with a specific SuperSpeed logo, and the ports themselves were often colored blue.

USB 3.1 arrived five years later and upped the ante again, raising the maximum transfer speed to 10Gbps using the SuperSpeed+ transfer mode. USB 3.1 Gen 2 is fast enough to drive even 10 Gigabit Ethernet connections.

Since the debut of USB 3.1, USB-IF decided to abandon the USB 3.0 name and use USB 3.1 Gen 1 to replace USB 3.0, both of which support 5Gbps transfer speed.

The USB 3.1 vs USB 3.0 difference remains almost exclusively bandwidth dependent. Both connectors operate the same whether using a more traditional USB-A or USB-B, or any of the various micro and mini USB connectors. Their generation is what's important, not the connector header.

That goes for USB-C connectors too, although you'll typically find USB-C devices support the faster USB 3.1, or even 3.2 standards- not always though. Many USB-C cables marketed as charging cables only support USB 3.0 or even 2.0 speeds. 

While USB 3.1 clearly wins the speed battle over USB 3.0, their successor outclasses both of them.

USB 3.2 and the future

The 3.0 vs 3.1 USB debate was settled for good with the release of USB 3.2. It preserved the existing SuperSpeed and SuperSpeed+ transfer modes of its predecessors and doubled the data transfer channels from a single lane to two lanes, doubling the max transfer rate to 20 Gbps.

Again, the USB 3.1 Gen 1 / Gen 2 naming convention became obsolete and was replaced by USB 3.2 Gen 1 / Gen 2

Full 20Gbps speeds are only possible with a USB-C cable, owing to the cable’s additional wires and pins. The USB-C connector will be maintained for the next-generation USB4 connector too. USB4 brings the data rate up to 40Gbps, in line with Thunderbolt 3. Other features include Power Delivery up to 100W to compatible devices, dynamic bandwidth sharing, and even Thunderbolt 3 connector compatibility. 

Better yet, it can put the confusion of USB 3.0 vs 3.1 vs 3.2 and their generations firmly in the rearview. Soon the battle won't be between 3.0 vs 3.1 USB devices, it'll be between USB4 and everything else – Thunderbolt 3 and 4 included.