What is the maximum data transfer speed that USB-C can achieve?

USB-C, also known as USB Type-C, is the future of wired connectivity. With its oblong, reversible connector, support for other technologies, and even more advanced features, USB-C aims to become a promising universal connector.

However, as transfer speed becomes increasingly important, the question is: How fast can USB-C reach?

When was USB-C launched? Is USB-C backward compatible?

What is the maximum data transfer speed that USB-C can achieve? Picture 1

The final USB-C specification was released in August 2014 and features a 24-pin reversible connector that can plug into the port in any orientation. USB-C's design allows it to deliver more power than previous generations, while also working in conjunction with other connectors like USB-A, USB-B, HDMI, DisplayPort, and 3.5mm audio jack.

The name USB-C only refers to the connector type/style, not the USB protocol it supports. Therefore, this same connector supports USB 2.0, USB 3.1 Gen 1 (USB 3.0), USB 3.1 Gen 2, USB 3.2 (and subsequent generations), USB4 and even Thunderbolt 3 and 4.

USB-C connectors are only slightly larger than micro-USB connectors and provide a connection that's thin enough for mobile devices yet strong enough for laptops and other power-hungry devices.

Although the USB-C connector itself is not backward compatible and you cannot plug a USB-C connector into a USB-A port, you can use an adapter to connect your USB-C devices to older USB ports. However, connectivity will be limited to the features provided by the USB-A or USB-B port.

USB-C data transfer standards

As mentioned earlier, USB-C currently supports different protocols and may include many more. These protocols typically support data transfer speeds from 480Mbps to 40Gbps. Higher speeds are theoretically possible but not yet exploitable. Two USB-C cables look similar but transfer data at speeds that can be very different.

1. USB 1.x : This is the first USB standard to hit the market. It can transfer data at 1.5 megabits per second (Mbps) at low speed and 12 Mbps at full speed. This generation allowed manufacturers to eliminate legacy ports such as serial and PS/2 ports from their computers, resulting in more compact and portable devices. Today, USB 1.x is largely deprecated, and USB-C cables support USB 2.0 at a minimum (but retain backward compatibility with USB 1.0).
2. USB 2.0 : Released in 2000, USB 2.0 improved upon the previous standard and increased the maximum data transfer speed to 480 Mbps.
3. USB 3.x : The third generation of the USB protocol has brought significant speed increases. USB 3.2 Gen 2 x 2 uses multi-lane signaling to achieve data transfer speeds of up to 20Gbps.
4. USB4 : USB4 is built to Thunderbolt 3 specifications and can tunnel other protocols such as PCie and DisplayPort. USB4 can achieve much faster speeds than USB 3.2, even with existing cables. The USB4 V2.0 specification further increased theoretical transfer speeds to 80 Gbps in bidirectional mode and 120 Gbps in asymmetric mode.
5. Thunderbolt 3 : This once-proprietary, now royalty-free standard from Intel also uses a USB-C connector. Thunderbolt 3 supports data transfer speeds of up to 40Gbps,
6. Thunderbolt 4 : It supports the same theoretical maximum transfer speed as USB4 and Thunderbolt 3 but increases the PCIe data requirement to 32Gbps from 16Gbps. There are some other differences between Thunderbolt 4 and USB4.

*: USB 3.0 was launched in 2008, then renamed USB 3.1 Gen 1 in 2013.

What is the maximum theoretical data transfer limit for USB-C?

The USB-C plug can transfer data at extremely fast speeds. USB4 is expected to be able to transfer data at speeds of 80Gbps and 120Gbps, although there are currently no products on the market that support this level. Additionally, future Thunderbolt 5 will likely support similar speeds.

However, currently, the highest data transfer speed you can get from a USB-C connection over both the USB4 and Thunderbolt 4 protocols is 40Gbps, and this speed is available on select Apple, Intel, and AMD laptops. launched after 2020. .

It's worth noting that these speeds are purely theoretical. Therefore, it is very likely that they will vary significantly during actual daily use. In the real world, USB devices sometimes exceed and even fall below these standards.

Some factors that can affect USB transfer speeds include cable length, cable quality, device compatibility (a USB 2.0 to USB 3.2 connection will operate at USB 2.0 speeds), interference and file type sent. Another consideration is the speed of the drive you are using. You will experience much faster data transfers when using a modern PCIe SSD compared to an older hard drive, regardless of the USB standard used.

There are several ways to increase USB data transfer speed on Windows that can be useful whenever you encounter very slow transfer speeds.

Jessica Tanner

Update 17 September 2023