USB4 represents the fifth generation of USB technology, published by the USB Implementers Forum in 2019. It uses the USB-C connector and delivers maximum theoretical bandwidth of 40 gigabits per second, making it twice as fast as USB 3.2.
The standard is built on Thunderbolt 3 protocol architecture, which means USB4 devices can achieve the performance benefits of Thunderbolt whilst maintaining backward compatibility with USB 3.2 and USB 2.0 connections. A single USB4 port can simultaneously carry multiple data streams: you might transfer files at high speed whilst streaming 4K video output to a display, for example.
Why USB4 matters: If you work with large video files, high-resolution photography, or external storage, USB4 eliminates the bottleneck of traditional USB speeds. It also reduces the need for multiple cables and adapters since one port handles multiple functions.
Practical considerations: USB4 adoption remains limited. Most mainstream laptops still ship with USB 3.2 or older. When shopping for USB4 devices, verify that both your device and any external storage or dock carry the USB4 logo, not just USB-C. Devices marketed as USB-C may only support older standards. Cables matter too: standard USB-C cables won't necessarily deliver full USB4 speeds.
You'll find USB4 adoption strongest in professional-grade laptops, high-end external drives, and premium docking stations. Budget and mid-range devices typically favour the cheaper USB 3.2 standard.