USB Standards (USB 1.1 to USB4 2.0 Comparison)

Compare USB versions 1.1, 2.0, 3.0, 3.1, 3.2, and USB4 by year, connector type, max transfer speed, and key features. A free reference that answers "what are the different types of USB?" with a search filter.

USB Standards Comparison Table
Standard Connector Year Max Transfer Speed Key Feature Current Status
USB 1.1 Type-A / Type-B 1998 12 Mbps The first widely adopted USB standard, used for connecting low-speed devices such as mice and keyboards. Has largely disappeared from today's consumer devices, remaining only for compatibility with legacy hardware.
USB 2.0 Type-A / Type-B / Mini-B / Micro-B 2000 480 Mbps Marketed as "Hi-Speed USB," it became the long-standing standard for a wide range of peripherals such as USB flash drives, external hard drives, and printers. Slow by today's standards, but still actively used for inexpensive mice, keyboards, and charge-only cables.
USB 3.0 Type-A / Micro-B / Type-C 2008 5 Gbps Often identified by blue-colored connectors and cables, this was the first SuperSpeed standard, offering roughly 10 times the theoretical speed of USB 2.0. Later renamed USB 3.1 Gen1 and then USB 3.2 Gen1 — the starting point of the naming confusion around USB 3.x.
USB 3.1 Gen2 Type-C 2013 10 Gbps Known as SuperSpeed+, it doubles USB 3.0's speed to 10 Gbps, and is mainly adopted with USB-C connectors. Later also called USB 3.2 Gen2. Commonly used for connecting fast external storage such as external SSDs.
USB 3.2 Gen2x2 Type-C 2017 20 Gbps Reaches a theoretical 20 Gbps by using two data lanes simultaneously — a standard supported only over USB-C connectors. Few devices and cables support it so far, and adoption remains limited as the industry moves toward USB4 instead.
USB4 Type-C 2019 40 Gbps Standardized based on Thunderbolt 3 technology, USB-C only, supporting up to 40 Gbps, DisplayPort Alt Mode, and up to 100W of power delivery. Adoption is growing, especially among Macs and high-performance laptops, as a unified connectivity standard for peripherals.
USB4 2.0 Type-C 2022 80 Gbps A further enhancement of USB4 using a new physical layer, reaching a theoretical 80 Gbps (or 120 Gbps in one direction only) — the latest standard. Compatible products have only just begun appearing since 2024 — widespread adoption is still ahead.

Tips

  • Even if a cable itself supports USB4, you won't get that speed unless the devices on both ends also support USB4. Check the cable, the devices, and the ports all together.
  • A USB-C connector shape alone doesn't tell you the internal standard (USB 2.0, 3.2, or 4) that a given cable supports, so you can't judge speed from the connector shape alone.
  • Fast charging (USB Power Delivery) requires a USB-C connector plus a matching combination of cable, charger, and device that all support it.
  • Ports for USB 3.0 and later are often colored blue inside, which lets you visually distinguish them from older USB 2.0 ports at a glance.
  • To get the full speed out of fast external storage like an SSD, choose a cable and port that support USB 3.2 Gen2 or later.

Frequently Asked Questions

USB 3.0 was later renamed USB 3.1 Gen1 and then USB 3.2 Gen1 — essentially the same 5 Gbps standard under different names. USB 3.1 Gen2 is a newer, higher-speed standard supporting 10 Gbps, and the renaming history is what makes the difference confusing.

USB4 was standardized based on Thunderbolt 3 technology and shares the same connector shape and some features, but Thunderbolt 4 is Intel's own certification standard that layers stricter mandatory requirements on top of USB4, such as a guaranteed minimum of 40 Gbps and mandatory external display support.

No. Even with the same USB-C connector, the internal standard supported (anywhere from USB 2.0 to USB4) and the power delivery capacity vary by cable, and some inexpensive cables are charge-only and don't support high-speed data transfer.

Most USB4 ports are backward compatible, so you can connect a USB 2.0 device using a Type-A-to-Type-C adapter, but the transfer speed will be limited to USB 2.0's 480 Mbps.

Since 2024, the USB PD standard supports up to 240W, which is used for fast-charging laptops, but the power adapter, cable, and device all need to support that wattage for it to work.
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Side Note — Why Is USB Naming So Confusing?

USB standard names have a history of repeatedly changing since they were first introduced. "USB 3.0," which debuted in 2008, was renamed "USB 3.1 Gen1" in a 2013 naming reorganization by the USB-IF (the industry group that develops USB standards), and then renamed again to "USB 3.2 Gen1" in 2017. The underlying transfer speed (5 Gbps) never changed, yet the name changed three times, causing widespread confusion among consumers about which standard was actually faster. Learning from this, the USB-IF has switched to simple generational names — "USB4" and "USB4 2.0" — for everything after USB4.

The real significance of the USB-C connector isn't just its smaller size — it's the reversible design that lets you plug it in either way up, and a mechanism called "Alternate Mode" that lets a single cable carry multiple protocols at once. Inside a USB-C cable, USB data signals, DisplayPort video signals, high-speed Thunderbolt data, and even high-wattage USB Power Delivery charging can all be carried simultaneously, letting one cable act like a dock — powering a laptop, driving an external display, and transferring peripheral data all at the same time.

With USB4 2.0 reaching a theoretical 80 Gbps, USB has largely caught up with the performance of Thunderbolt, a standard originally championed by rivals Apple and Intel. In fact, USB4 itself was standardized based on Thunderbolt 3 technology, and the technical gap between the two keeps narrowing each year. Going forward, the physical connector shape (USB-C) is likely to stay the same while the underlying protocol keeps getting updated in software, making it more important for consumers to check the supported standard of their cables and devices rather than just the connector shape.