Decoding USB Generations

Decoding USB Generations

In the ever-evolving landscape of technology, understanding the intricacies of USB standards and their various generations can be a daunting task. With numerous updates and revisions over the years, it’s crucial to unravel the differences as the names alone don’t help much; USB 3.0, 3.1 Gen 1, 3.1 Gen 2, 3.1 Gen 2 x2 etc. Let’s delve into the world of USB (Integral Memory USB Flash Drives) standards to shed light on these distinctions and equip you with the knowledge you need to navigate this realm effectively.

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USB 3.0 to USB 3.1 Gen 1

USB 3.0 made its debut in 2008, marking the third major revision to the USB standard. This groundbreaking release represented a significant leap forward from USB 2.0, which had been the prevailing standard since its introduction in 2000, offering only 480 Mbit/s transfer speeds. USB 3.0 revolutionised connectivity with its impressive data transfer rates of up to 5 gigabits per second (Gbps). However, as technology progressed, USB 3.0 evolved into USB 3.1 Gen 1, maintaining its capabilities but adopting a new name under the oversight of USB-IF (USB Implementers Forum), the organisation responsible for USB standards and compliance.

USB 3.1 Gen 1 vs. Gen 2

The primary distinction between USB 3.1 Gen 1 and Gen 2 lies in their data transfer speeds. USB 3.1 Gen 1 supports speeds of up to 5 Gbps, while USB 3.1 Gen 2 boasts doubled speeds, allowing for transfers at 10 Gbps. Initially, USB-IF attempted to introduce the terms “SuperSpeed” and “SuperSpeed Plus” to differentiate between Gen 1 and Gen 2, respectively. However, these terms failed to gain widespread acceptance, and the industry largely refers to them as USB 3.1 Gen 1 and USB 3.1 Gen 2.

USB 3.2

In 2017, USB-IF introduced USB 3.2 embracing the capabilities of the USB-C connector, offering higher transfer speeds and faster charging. USB 3.2 comes in four variations, each with its unique specifications:


USB 3.2 Gen 1×1: Maintains the 5 Gbps transfer speed and supports USB-A, USB-C, and microUSB interfaces.

USB 3.2 Gen 1×2: Doubles the potential transfer speed to 10 Gbps with an additional data lane, available only in USB-C form factor.

USB 3.2 Gen 2×1: Supports 10 Gbps transfer speeds across USB-A, USB-C, and microUSB interfaces.

USB 3.2 Gen 2×2: Offers the potential for 20 Gbps transfer speeds, exclusively through USB-C connections.

Looking Towards the Future: USB4 and Beyond

In 2019, USB-IF published the standard for USB4. With blazing-fast 40 Gbps transfer speeds and Thunderbolt 3 compatibility, USB4 aims to streamline the USB-C ecosystem and minimise user confusion. USB4 represents a convergence of USB and Thunderbolt products, offering a universally compatible and versatile solution for future connectivity needs.

                                                                                    Comparison Table

Specification NameFormer NameTransfer SpeedInterface
USB 2.0 480MbpsUSB-A, USB-B, microUSB, miniUSB
USB 3.1 Gen 1 x1

USB 3.0

USB 3.1 Gen 1

5GbpsUSB- A, USB-B, USB-C, microUSB
USB 3.1 Gen 2 x1 10GbpsUSB- A, USB-B, USB-C, microUSB
USB 3.2 Gen 1 x1

USB 3.0

USB 3.1 Gen 1 x1

5GbpsUSB- A, USB-C, microUSB
USB 3.2 Gen 1 x2 10GbpsUSB-C
USB 3.2 Gen 2 x1USB 3.1 Gen 2 x110GbpsUSB- A, USB-C, microUSB
USB 3.2 Gen 2 x2 20GbpsUSB-C
USB 4 40GbpsUSB-C
USB 4 version 2 80GbpsUSB-C


The additional ‘x1’ ‘x2’ on the USB names refers to the number of data lanes available.