The USB standard is now used to connect most devices. However, when you decide to buy a USB cable or a device that uses this technology, you can get a little confused due to the presence of numerous USB standards. In this article, we will have a detailed look at the difference between USB 3.0, 3.1, and 3.2.
The USB 1.0 and 2.0 standards will not be mentioned, as I believe the latter are now obsolete. To tell the truth, many still use USB 2.0 on many devices, but in most cases, these are not storage devices that require a high transfer rate.
What are the differences between USB 3.0, USB 3.1, and USB 3.2?
USB 3.0
The USB 3.0 Super-Speed standard was released between 2009 and 2010, allows to reach a theoretical speed of 4.8 Gbps, and is backward compatible with 2.0 and 1.0 standards.
Super-Speed is the name of the BUS, the latter allowing a real transfer speed of 3.2 Gbps (400 MB / s).
The USB 3.0 connectors and ports have more PINs than the old versions and are easily recognizable thanks to their blue color and the writing “SS.”
USB 3.1
The USB 3.1 Super-Speed + standard was introduced in 2013. It is also available in two types: USB 3.1 Gen1 and USB 3.1 Gen2.
USB 3.1 Gen1 guarantees a theoretical speed of 5 Gbps, therefore the same as version 3.0. USB 3.1 Gen 2 allows a theoretical transfer speed of 10 Gbps, equal to 7.2 Gbps (900 MB / s).
To do a little more clarity, the true USB 3.1 standard is the Gen2 one. The Gen1 version is, in fact, identical to the previous one. Put simply, USB Gen1 was just a marketing choice, thanks to which device and PC manufacturers were able to rename their product ports “USB Gen1” when in reality, they were USB 3.0 ports.
In the USB 3.1 Gen2 connectors, you will always find the suffix “Gen2.” In the USB 3.1 Gen1 ports, you can only find the writing “USB 3.1” or the suffix “Gen1.”
USB 3.2
The USB 3.2 standard was introduced in 2019. It also gives room for a theoretical transfer speed of 20 Gbps.
However, with the release of version 3.2, things get even more complicated, and the confusion increases. The USB Implementers Forum consortium (the organization that oversees the development and certification of products) has well thought of re-grouping different standards with the same ending. Again, I think it was a mere marketing issue.
So we find the following suffixes:
- USB 3.2 Gen1: This is the USB 3.0 standard
- The USB 3.2 Gen2: is the previous standard (USB 3.1)
- USB 3.2 Gen 2 × 2: This is the true USB 3.2 standard
To fully exploit the potential of the USB 3.2 standard, the USB Type-C ports must be used. The USB 3.2 type A connectors (the classic ones to be clear) will not reach the speed of 20 Gbps.
Conclusions
For greater clarity, below you will find a summary diagram that will allow you to understand which USB standard you are dealing with quickly:
- USB 3.0 (maximum speed 5Gbps): SuperSpeed USB, USB 3.1, USB 3.1 Gen1, USB 3.2 Gen1 or USB 3.2 Gen 1 × 1
- The USB 3.1 (10Gbps max speed): USB 3.1 Gen2, USB 3.2 Gen2, USB 3.2 Gen 2 × 1
- USB 3.2 (max speed 20Gbps): USB 3.2 Gen 2 × 2
