If someone needs to buy a USB-C or Thunderbolt 3 cable right now they might as well buy a universal Thunderbolt 4 cable since it is backwards compatible with everything, and they have the benefit of future-proofing their cable.
What is Thunderbolt 4?
Thunderbolt 4 is the latest version of Intel’s Thunderbolt line. It is backwards compatible with Thunderbolt 3 and USB-C, and has a range of benefits. All certified Thunderbolt 4 cables work with everything, including USB4, USB 3.2, USB 3.1, and even USB 2.0—no matter what their length. Thunderbolt 4 allows for up to 40Gbps data transfer, 100W power delivery (PD) and laptop charging. This was true of Thunderbolt 3, but some Windows PC and laptops used cut-down versions. To be officially certified as Thunderbolt 4 by Intel, all manufacturers have to supply the top specifications TB4 offers. Some are now certified to work with up to 240W charging. That’s why we recommend Thunderbolt 4 cables even if you don’t yet own a TB4 computer. TB4 can also support high-resolution displays up to 8K (7,680-x-4,320) or any USB-C monitor. Buying a USB-C display means you can use a Thunderbolt 4 cable that’s much thinner than a DisplayPort or HDMI cable. It can also be used with many devices other than displays, unlike video cables. Previously, 2m cables could not be used with USB-C monitors—a limitation rectified by Thunderbolt 4.
Thunderbolt 4 benefits
Support for two 4K displays or one 8K display40Gbps bandwidthPCIe at 32Gbps for data-storage speeds up to 3,000MBpsSupport for docks with up to four Thunderbolt 4 ports100W PD charging on at least one computer port (up to 240W when certified PD 3.1)Wake the computer from sleep by touching the keyboard or mouse when connected to a Thunderbolt dockIntel VT-d direct memory access (DMA) protection to prevent physical DMA attacks
Like Thunderbolt 3, Thunderbolt 4 ports and cables show the small lightning bolt logo, which helps to differentiate TB4 from USB4 and older USB-C 3.2 ports. Thunderbolt 4 cables include a small number 4 underneath the lightning bolt logo.
What is USB4?
USB4 takes over from the often confusing USB 3.0 to 3.2, offering either 20Gbps or 40Gbps data speeds. It uses the same rounded, reversible Type-C connector as USB-C, Thunderbolt 3 and 4. A Thunderbolt 4 cable is also a USB4 cable, but not all USB4 cables will be certified for use with Thunderbolt 4 or even Thunderbolt 3—which is another reason that a TB4 cable is our universal recommendation. USB4 has lower minimum requirements than Thunderbolt 4 and doesn’t offer all the benefits such as support for dual displays, so its cables are often cheaper, acting more like Thunderbolt 3. That said, USB4 is certainly more efficient than older USB variants at sharing between data and display protocols as it can dynamically monitor bandwidth requirements for connected displays and save the remaining bandwidth for data transfer. Older USB simply split the bandwidth in two for display and data. USB4 can support Power Delivery up to 100W (PD 3.0) or 240W (PD 3.1). And, like Thunderbolt 4, USB4 is backwards compatible with USB 3.2, USB 3.1, USB 3.0, USB 2.0, and Thunderbolt 3. A certified USB4 cable will feature the USB logo plus either the number 20 or 40 depending on the speed (20Gbps or 40Gbps) it is rated at. More details are available on Thunderbolt 4 vs Thunderbolt 3 vs USB4.
Thunderbolt 4 / USB4 cables: length
“Passive” Thunderbolt 3 cables reduced in data-transfer rate as they got longer. Anything over 1m and the bandwidth could be reduced to 20Gbps unless the cables were “Active” including special signal boosters at each end, but this significantly increased the cost. Thunderbolt 4 cables can be up to 2m in length and still reach 40Gbps without the need for expensive Active boosters. Anything over 2m and you need an Active TB4 cable to maintain the high data rate.
0.8m Passive Thunderbolt 3 cable: 40Gbps data transfer rate1m or 2m Passive Thunderbolt 3 cable: 20Gbps data transfer rate1m or 2m Active Thunderbolt 3 cable: 40Gbps data transfer rate1m or 2m Passive Thunderbolt 4 cable: 40Gbps data transfer rate1m Passive USB4 cable: 40Gbps data transfer rate2m Passive USB4 cable: 20Gbps data transfer rate
Thunderbolt 4 / USB4 cables: charging
Thunderbolt 4 cables support 100W (USB-C PD 3.0) charging as standard. You can attach a powerful wall charger up to 100W, but note that Thunderbolt and USB-C charging functionality is dependent on your host computer’s charging capabilities. Some Windows PC manufacturers limit charging on their ports. Either way, a TB4 cable is capable of the maximum 100W. USB-C PD 3.1 now allows for charging at up to 240W. If your device supports charging at over 100W, you’ll need a PD 3.1 cable that supports 240W. This is noted in our reviews below. Many 240W cables are for charging only, so have a very low data-transfer rate at 240Mbps—so a Thunderbolt 4 or USB4 240W cable is far more adept as your principal cable, say between a laptop and a Thunderbolt dock. Here are the best Thunderbolt 4 and USB4 cables available today.
Thunderbolt 4: Active or Passive?
USB-C and Thunderbolt cables can be either “Passive” or “Active”.
40Gbps
Short
Type: Passive, 40Gbps Charging: 100W Caldigit’s shortest and most affordable Thunderbolt 4 / USB4 cable measures 0.8m, which is about 2.6 feet. It is Intel certified, and of a quality you can expect from one of the leading Thunderbolt dock, hub and accessory manufacturers, built with premium materials to maintain consistent performance and reduce heat. It includes E-Marker chips at either end of the cable, which communicate with attached devices to provide the correct amount of power in order to prevent damage to your devices caused by an excess of power. It is backwards compatible with Thunderbolt 3, USB4, USB 3.2, USB 3.0 and USB 2.0.
40Gbps Very long Active Braided
Expensive
Type: Active, 40Gbps Charging: 100W At 3m (nearly 10ft) in length, Apple sells the longest Thunderbolt 4 cable you can get. As such you will pay a premium but if you need the longest cable, this is the only show in town right now. It’s nicely braided and promises not to tangle when coiled. Who needs a 3m Thunderbolt cable? Most computers are within a metre or two of the docking station, screen or other connected devices so it’s probably aimed at a professional production setting where an external device, such as shared storage, isn’t close by,
40Gbps Long Active
Type: Active, 40Gbps Charging: 100W If you need a long Thunderbolt 4 or USB4 cable, look for a 2m length. Thanks to the magic of Thunderbolt 4, such a long cable doesn’t need to be “active” to keep its full data load at this length, but this cable does boast boosters to keep the signal strong from one end to the other. Like its 0.8m TB4/USB4 cable, the 2m cable is backwards compatible, features E-Marker technology and has a two-year warranty.
40Gbps 240W charging
Type: Passive, 40Gbps Charging: 240W Larger modern laptops can now support faster charging through 140W or higher chargers, thanks to the latest USB PD 3.1 standard that allows for up to 240W charging. This Thunderbolt 4 cable from Plugable supports PD 3.1, as well as offering all the top-end benefits of Thunderbolt 4. Your device will also need to support PD 3.1 to gain the full benefit, but it is backwards compatible with PD 3.0 so will also work with 100W and lower devices.
40Gbps 240W charging
Type: Passive, 40Gbps Charging: 240W If your laptop or other device supports faster 140W-plus charging, this USB PD 3.1-ready USB4 cable is certified to reach up to 240W. Like Plugable’s Thunderbolt 4 240W EPR Cable, it is backwards compatible with PD 3.0 so will also work with 100W and lower devices.
40Gbps Long Braided
Expensive
Type: Passive, 40Gbps Charging: 100W Apple’s Thunderbolt 4 Pro cable is braided in a design that it claims will coils without tangling, which is a joy with any cable. It’s more expensive than most, but that’s Apple for you. You can buy 2m cables for a lot less from other manufacturers.
40Gbps
Short
Type: Passive, 40Gbps Charging: 100W Cable Matters, as its name suggests, is something of a specialist in cables, and it offers a 0.8m Thunderbolt 4 / USB4 cable that is Intel certified, backwards compatible, and capable of all the advantages of the new TB4 standard. Its TB4/USB4 cables feature active repeater chips that boost the signal, preserving full 40Gbps performance.
40Gbps Long Active
Type: Active, 40Gbps Charging: 100W 0.8m length is probably fine to connect your laptop or PC to a nearby docking station, but it might be too short to connect to that second or third display. Cable Matters sells an Intel-certified 2m Thunderbolt 4 cable that is also compatible with USB4. It’s an Active cable so has a chipset that boosts the data signal along such a long distance. Thunderbolt 4 should allow for 40Gbps data transfer at up to 2m but the active nature of this cable is reassuring at this length. 2m should be enough if you need to link to a device, such as a monitor, that is some distance from your laptop or docking station.
40Gbps White
Short
Type: Passive, 40Gbps Charging: 100W All credit to Ugreen for selling a USB4 cable in a color other than black. This 40Gbps USB4 cable offers all the top USB4 benefits from a trusted accessory provider.
40Gbps
Short
Type: Passive, 40Gbps Charging: 100W While Thunderbolt 4 cables are compatible with USB4, not all USB4 cables work with Thunderbolt 4 but this one does. This premium cable is certified to work with USB4 at full 40Gbps bandwidth.
40Gbps
Short
Type: Passive, 40Gbps Charging: 100W OWC makes quality accessories, targeted especially at users of Apple products. Its Thunderbolt 4 and USB4 cable is universal and certified by Intel, but available from 0.7 metres in length. There are also 1m and 2m cables available. It has a three-year guarantee and is compatible with USB-C, Thunderbolt 3 and, of course, Thunderbolt 4.
40Gbps Long
Type: Passive, 40Gbps Charging: 100W This OWC Thunderbolt 4 cable is 2m long, works with USB4 and is backwards compatible with Thunderbolt 3 and USB-C. Its three-year guarantee should give you confidence in its longevity.
40Gbps
Short
Type: Passive, 40Gbps Charging: 100W The Plugable 1M (3.2ft or 1m) Thunderbolt 4 and USB4 cable is Thunderbolt certified to ensure 100W 20V/5A Power Delivery, 40Gbps data transfer speeds, and support for two 4K screens or one 8K screen. It comes with a two-year warranty.
40Gbps Long Active
Type: Active, 40Gbps Charging: 100W Just like its half-shorter sibling, the 2m (6.4ft) Plugable Thunderbolt 4 and USB4 cable is fully certified, and long enough to stretch the full length of your desk. It’s an active cable, meaning the data signal is boosted to ensure it doesn’t degrade over the 2m length.
40Gbps
Short
Type: Passive, 40Gbps Charging: 100W Spigen makes decent cables and has its own 0.8m USB4 and Thunderbolt 4 cable in the mandatory black, although oddly without the 4 icon branding. The company claims that its Durabend Technology means that the cable has a 10,000+ “Bend Lifespan”.
40Gbps
Short
Type: Passive, 40Gbps Charging: 100W Anker’s Thunderbolt 4 cable is a little shorter than most at 0.7m (2.3ft), but it’s fully Intel certified, and might attract users who don’t need a cable any longer. Sometimes a shorter cable is just better to eliminate cable clutter. An active cable includes small electronic circuits (called retimers) that boost the intensity of the data carried by the cable, which can stop signal degradation due to the length of the cable. This is why they cost more than simpler passive cables that merely carry data that’s transferred through them but at an ever slower rate the longer the distance. Data can travel only so far before the integrity of the signal starts to degrade—and the faster the data is running, the faster that degradation occurs. In the previous generation, it was important to distinguish between Passive and Active for backwards compatibility, but with Thunderbolt 4 it’s not as much of a consideration since all TB4 cables are backwards compatible with Thunderbolt 3, USB4, USB 3.0, USB 2.0 etc—unlike Thunderbolt 3 active cables that were backwards compatible with only USB 2.0 (at a rather pathetic 480MBps). With Thunderbolt 3, cables as long as 2m had to be active to hit 40Gbps bandwidth. The maximum length of a passive Thunderbolt 3 cable is just 0.8m at full 40Gbps bandwidth, or 2m at 20Gbps bandwidth. • USB speeds explained USB-IF, the official USB Implementers Forum, dictates that passive USB 3.2 Gen 1 (5Gbps) cables should be at most 2 metres, while USB 3.2 Gen 2 (10Gbps) cables can reach only up to 1 metre if it is to keep transferring data at its maximum speed. However, an active USB-C 3.2 Gen 2 cable can be up to 3m in length. With Thunderbolt 3, only passive cables were backwards compatible, meaning longer active TB3 cables worked with Thunderbolt devices only. In comparison, even 3m Thunderbolt 4 cables support all versions of USB, so buying Thunderbolt 4 will future-proof your cable purchase as well as offer backwards compatibility. With a TB4 cable, you gain the versatility to connect USB-C devices to Thunderbolt ports. In addition, since Thunderbolt 4 supports USB4, if someone needs a USB4 cable they can use a Thunderbolt 4 cable. One of the benefits of Thunderbolt 4 cables for USB4 users is that Thunderbolt 4 cables always support up to 40Gbps—USB4 is rated at either 20Gbps or 40Gbps, so TB4 is ready for both. While a Thunderbolt 4 cable can be passive even at 2m, some are active, and we have stated this in the reviews below where appropriate.
Thunderbolt 4 devices
While a Thunderbolt 4 cable will work with older Thunderbolt 3 and USB-C devices, new Thunderbolt 4 docking stations and hubs are available to take advantage of the ability to include multiple TB4 ports. The Caldigit Element Hub boasts four Thunderbolt 4 ports (and four 10Gbps USB-A ports!). The OWC Thunderbolt Hub and Anker Apex Thunderbolt 4 Dock also include four TB4 and extra USB-A ports. Read our tests and reviews of the best Thunderbolt 4 and USB4 hubs and docks. Simon was Editor of Macworld from the dark days of 1995 to the triumphant return of Steve Jobs and the launch of the iPhone. His desk is a test bench for tech accessories, from USB-C and Thunderbolt docks to chargers, batteries, Powerline adaptors and Fitbits.
