USB Reference
USB Standards
USB standards define how USB data connections operate across generations. Connector shape is separate from the USB data standard.
USB standards comparison
Compare the major USB generations by maximum data rate, key change, and current status.
| Standard | Maximum data rate | Key change | Current position |
|---|---|---|---|
| USB 1.x | 12 Mbps | Original Low-Speed and Full-Speed USB | Legacy |
| USB 2.0 | 480 Mbps | High-Speed USB | Still widely supported |
| USB 3.0 | 5 Gbps | Introduced SuperSpeed USB | Historical revision within USB 3.2 |
| USB 3.1 | 10 Gbps | Added 10 Gbps operation | Historical revision within USB 3.2 |
| USB 3.2 | 20 Gbps | Added two-lane 20 Gbps operation | Current USB 3.x family |
| USB4 | 40 Gbps originally | USB-C architecture with data/display protocol sharing | Current family |
| USB4 Version 2.0 | 80 Gbps | Higher-performance USB4 signaling | Current USB4 specification generation |
Sources: USB-IF USB 2.0 Specification, USB-IF USB 3.2, and USB-IF USB4.