Here’s the short answer… USB 3.0 is 5Gb/s, USB 3.1 is 10Gb/s, and USB 3.2 is the fastest at 20Gb/s. You may have seen them branded as SuperSpeed USB 5Gbps/10Gbps/20Gbps. The only thing you need to pay attention to is the transfer speeds. Manufacturers with clever marketing can manipulate the naming schemes to make you think you’re getting a product you aren’t. Read more to find out the differences between USB 3.0 vs 3.1 vs 3.2!
Data transfer speeds are rated in megabytes per second (MBps). Don’t confuse this with megabits per second (Mbps). 1 byte of data contains 8 bits. So 1 megabyte is 8 megabits. For perspective, phone camera photos in late 2021 are around 2 megabytes (MB). A little bit of math, 2MB transferring at a speed of 1MBps would take 2 seconds to transfer. Here’s a great article on Bytes vs Bits.
History, Encoding, and Speeds of USB 3.0, 3.1, and 3.2
USB 3.0 and USB 3.1
In 2013, the USB Implementers Forum (USB-IF) announced that they would be increasing the speed of USB 3.0 to 1,250MBps from 600MBps. Instead, they renamed the 600MBps USB 3.0 to “USB 3.1 Gen 1” and gave “USB 3.1 Gen 2” as the name to the faster 1,250MBps standard. This makes an easy differentiation between the old encoding signal, named “8B/10B”, and the new encoding signal, named “128B/132B”. Anything with the old encoding standard is listed as USB 3.0. Any of the newer encoding standards, even if the speeds are slower, are listed as USB 3.1.
- USB 3.0 = 600MBps, 8B/10B signal
- USB 3.1 Gen 1 = 600MBps, 128B/132B signal (Formerly USB 3.0 speed, new encoding signal)
- USB 3.1 Gen 2 = 1,250MBps, 128B/132B signal (Faster speed, new encoding signal)
When you are looking at a listing for USB 3.1 devices, make sure you check the transfer speed as well. Just because the label says USB 3.1 doesn’t mean you’re getting a faster flash drive or device. Manufacturers can advertise products with the slower speed (600MBps) as USB 3.1 and not specify which generation.EBS Helpful Tip
USB 3.2 was launched in 2017. The new transfer speeds boast an impressive 2.4GBps making it almost 2.5x faster than USB 3.0. USB 3.2 is only available on USB-C connectors because it utilizes extra pins that were designed for the reversibility of USB-C. The USB family naming system was updated again which differentiates between the new transfer modes.
- USB 3.2 Gen 1×1 = 600MBps, 8B/10B signal (Formerly USB 3.0)
- USB 3.2 Gen 2×1 = 1,250MBps, 128B/132B signal (Formerly USB 3.1 Gen 2)
- USB 3.2 Gen 2×2 = 2.4GBps, 128B/130B signal, Dual-Lane (USB-C Only)
USB Connectors and Backwards Compatibility
As mentioned before, USB-C is the only connection type that can carry the new USB 3.2 Gen 2×2 rating. But, USB-A, B, and micro B can all carry the USB 3.2 Gen 2×1 and prior versions.
Although USB-C is backward compatible, it only more recently has been added to the hardware of newer computers and peripherals. So you may be in luck with your devices being equipped with USB-C and USB 3.2 Gen 2×2 I/O ports.
Note that even if the cable and connector you use are rated at a certain speed, the host and receiver of the data must also be able to send or receive at that speed. The point with the slowest rating controls the speed of the transfer. There are very few computers that support USB-C at the highest speed. Most computers and peripherals are still only using USB 10Gbps cables and I/O connectors.
Recommended Marketing Name and Logos
The USB-IF recommends these more market friendly names to the USB standards:
- SuperSpeed USB 5Gbps – USB 3.2 Gen 1×1 / USB 3.0
- SuperSpeed USB 10Gbps – USB 3.2 Gen 2×1
- SuperSpeed USB 20Gbps – USB 3.2 Gen 2×2
If you see these more friendly terms around, you know what speed you’re getting.
The differences may be confusing but the key thing to remember is that the noticeable differences are in speed. As files get larger and larger make sure you have devices that can handle the media you are creating! Shop USB Flash Drives and USB External Hard Drives on our Shop page.
When referring to “USB” remember that you are referring to a bus. A bus is the way data moves between parts of a computer. Although many cables and connectors have USB in the name, unless there is a letter following it, the USB is just a bus. USB can refer to more than just what’s on a flash drive. For example, an external hard drive, a webcam, and other peripherals use USB to interface with your computer. That being said, most of the scenarios in this blog are regarding USB flash drives with either USB-A or USB-C connections.
Data encoding is the process of converting data into a string of 1’s and 0’s to be sent from a host to a receiver. Encoders use different ways to verify the information to protect it from errors. Sometimes this process can cause the data transfer to slow down. Encoding signals measure as a set of alphanumeric characters divided by a slash.