USB4 Specification Merges Thunderbolt 3 and USB With Transfer Speeds up to 40Gb/s
The USB4 specification for a new version of USB was today published by the USB Implementers Forum [PDF] giving us details on what to expect from the next-generation USB architecture following a preview back in March.
USB4 is a major update that "complements and builds upon" the current USB 3.2 2x2 (USB-C) and USB 2.0 architectures. According to the USB-IF, the USB4 architecture is based on Thunderbolt, doubling the maximum bandwidth of USB and allowing for multiple simultaneous data and display protocols.
The USB-IF outlined key specifications of the USB4 architecture, such as 40Gb/s speeds (twice the current 20Gb/s maximum) and backwards compatibility with USB 3.2 and Thunderbolt 3.
- Two-lane operation using existing USB Type-C cables and up to 40Gbps operation over 40Gbps certified cables
- Multiple data and display protocols that efficiently share the maximum aggregate bandwidth
- Backward compatibility with USB 3.2, USB 2.0 and Thunderbolt 3
USB4 will use the same USB-C connector design as USB 3, which means manufacturers will not need to introduce new USB4 ports into their devices.
Apple's newest Macs offer support for USB-C and Thunderbolt 3, which means most Mac users are already experiencing USB4 speeds when using Thunderbolt 3 cables and devices, but USB4 will make Thunderbolt-style speeds the new default and it will lower the cost of devices that use these faster transfer speeds.
USB Power Delivery will be required in devices built for USB4, which also means we can expect to see higher-powered chargers with multiple USB4 ports.
Though the USB4 specification is complete, it will still be some time before we can expect to see devices that take advantage of USB4. It typically takes at least a year for new products to come out following the finalization of a new specification, so it will be late 2020 or beyond before we begin seeing USB4 devices.
Popular Stories
iOS 27 is still many months away, but there are already plenty of rumors about new features that will be included in the software update.
The first beta of iOS 27 will be released during WWDC 2026 in June, and the update should be released to all users with a compatible iPhone in September.
Bloomberg's Mark Gurman said that iOS 27 will be similar to Mac OS X Snow Leopard, in the sense...
Apple is planning to debut a high-end secondary version of AirPods Pro 3 this year, sitting in the lineup alongside the current model, reports suggest.
Back in September 2025, supply chain analyst Ming-Chi Kuo reported that Apple is planning to introduce a successor to the AirPods Pro 3 in 2026. This would be somewhat unusual since Apple normally waits around three years to make major...
MacBook Pro availability is tightening on Apple's online store, with select configurations facing up to a two-month delivery timeframe in the United States.
A few 14-inch and 16-inch MacBook Pro configurations with an M4 Pro chip are not facing any shipping delay, but estimated delivery dates for many configurations with an M4 Max chip range from February 6 to February 24 or even later. At...
While the iPhone 18 Pro and iPhone 18 Pro Max are not expected to launch for another eight months, there are already plenty of rumors about the devices.
Below, we have recapped 12 features rumored for the iPhone 18 Pro models, as of January 2026:
The same overall design is expected, with 6.3-inch and 6.9-inch display sizes, and a "plateau" housing three rear cameras
Under-screen Face ID...
Over the last few months, rumors around the iPhone 18 Pro's front-panel design have been conflicted, with some supply-chain leaks pointing to under-display Face ID, reports suggesting a top-left hole-punch camera, and debate over whether the familiar Dynamic Island will shrink, shift, or disappear entirely.
Today, Weibo-based leaker Instant Digital shared new details that appear to clarify the ...
