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01Same speed, same plug, different badge
In the USB4 vs Thunderbolt 4 cable debate, the speed is a tie: both top out at 40Gbps over a USB-C plug. Thunderbolt 4 is Intel's certification built on the same foundations as USB4, with stricter minimums for the devices and cables that carry the logo.
USB4 is the USB-IF's standard. It allows a range of capabilities: 20Gbps or 40Gbps, with some features optional for device makers. Thunderbolt 4 takes the top USB4 tier and makes it mandatory. Every Thunderbolt 4 cable supports 40Gbps, and every certified one is tested to work as a USB4 cable, a Thunderbolt 3 cable and a regular USB-C cable. That's the whole argument for Thunderbolt in one sentence: fewer surprises.
Both also carry video. A 40Gbps USB4 or Thunderbolt 4 cable can drive external monitors from a laptop that supports it, and both pass USB Power Delivery for charging. So for most desk setups the question isn't capability. It's whether the cable will reach and whether it's certified to behave.
02Spec sheet, side by side
| USB4 40Gbps cable | Thunderbolt 4 cable | Thunderbolt 5 / USB 80Gbps cable | |
|---|---|---|---|
| Top data speed | 40 Gbps | 40 Gbps | 80 Gbps |
| Passive length at full speed | Usually up to 0.8 m | Up to 2 m | Short; check the listing |
| Charging | Typically 60W, 100W or 240W, as labeled | At least 100W | Often 240W, as labeled |
| Works with Thunderbolt 3 devices | Usually | Yes | Yes |
| Works with plain USB-C phones and chargers | Yes | Yes | Yes |
| Certification | USB-IF (logo shows speed and watts) | Intel Thunderbolt | Intel or USB-IF |
Length is where you'll notice the difference. Getting 40Gbps over a passive cable is hard, so USB4 cables at that speed are usually short, around 0.8 m (about 2.6 ft). Thunderbolt 4 brought 2 m passive cables, which is enough to reach a monitor or dock that isn't sitting right next to the laptop. Longer runs at full speed need active cables with signal boosters in the plugs, which cost more.
Charging is the other place to read the label carefully. Thunderbolt 4 cables are required to carry at least 100W, so any of them will charge a typical laptop. USB4 cables are certified with a wattage printed alongside the speed, and a 60W USB4 cable is a real thing. If the cable will also power a laptop over 60W, make sure the packaging shows 100W or 240W.
03Which cable fits your setup
Thunderbolt 4
- 40Gbps guaranteed
- 2 m passive option
- Works with Thunderbolt 3, USB4 and USB-C
- Costs more
USB4 40Gbps
- Same 40Gbps on USB4 laptops
- Usually 0.8 m or shorter
- Check the watt label for charging
Standard USB-C
- 60W to 240W charging
- USB 2.0 data is plenty for phones
- Cheaper, longer, more flexible
A practical rule: if the thing you're connecting has a Thunderbolt logo next to its port, buy a Thunderbolt cable. If it's a USB4 laptop with a USB4 dock on your desk, a short USB4 40Gbps cable does the same job. And if you're only charging, the data speed is irrelevant, so buy on wattage. Our USB-C cable types explainer breaks down every tier.
04Do phones benefit? Barely
Phones sit far below these speeds. The iPhone 15 Pro, 16 Pro and 17 Pro models support USB 3 at up to 10Gbps, and many Android flagships use USB 3 speeds too. Standard iPhones and many other phones run at USB 2.0 (480 Mbps). Plug a Thunderbolt 4 cable into any of them and it works, but only at the phone's own speed.
+Using one with your phone
- Charges at full speed, since it carries 100W or more
- Handles 10Gbps transfers from Pro iPhones
- One cable shared with your laptop
–Why it's usually overkill
- Several times the price of a phone cable
- Short and stiff for bedside or car use
- No speed gain over a 10Gbps cable
A pricier cable doesn't make a phone charge faster. Charging speed comes from the charger and the phone's limits, and almost any USB-C to USB-C cable carries the 60W phones need. Galaxy phones with 45W or 60W modes are the one exception: they need a 5A cable, which any 100W or 240W cable provides. See what is an e-marker cable.
05Buying tips that save money
- Buy for the most demanding device. A laptop dock sets the spec; the phone just goes along.
- Read both numbers. Certified USB cables show speed and watts, like "USB 40Gbps / 240W". Missing one means it wasn't certified for it.
- Keep it short for speed. At 40Gbps and up, shorter passive cables are more reliable.
- Own one fast cable, not five. Leave it with the dock and use cheaper charging cables everywhere else.
For the everyday cables, charging speed is what counts, and a good charger matters more than anything. How to choose a wall charger covers the brick, and USB-C cable not charging helps when one quits.
For phones, tablets and laptop charging. These are rated by wattage, not Thunderbolt data speeds.
Questions people ask
Can I use a Thunderbolt 4 cable for USB4?
Yes. Certified Thunderbolt 4 cables are tested to work as USB4 40Gbps cables, as well as with Thunderbolt 3 and ordinary USB-C devices. That's why they're the safest single cable to buy for a laptop setup.
Can I use a USB4 cable with a Thunderbolt 4 laptop?
Usually, yes. A USB4 40Gbps cable will normally run Thunderbolt at full speed. A 20Gbps USB4 cable will connect but at lower speed. For guaranteed results, a certified Thunderbolt cable removes the guesswork.
Is Thunderbolt 4 faster than USB4?
Not at the top end. Both reach 40Gbps. The difference is that every Thunderbolt 4 cable must hit that speed, while USB4 cables can be rated for 20Gbps or 40Gbps.
Will a Thunderbolt cable charge my phone faster?
No. Charging speed depends on your charger and phone. Any standard USB-C cable carries the 60W phones use. Galaxy phones with 45W or 60W modes need a 5A cable, but any 100W cable does that without Thunderbolt's price.
What's the difference between Thunderbolt 4 and Thunderbolt 5 cables?
Thunderbolt 5 doubles the speed to 80Gbps, with a boost mode for displays. Thunderbolt 5 cables work with Thunderbolt 4 and USB4 devices too. Unless you have a Thunderbolt 5 laptop and dock, a Thunderbolt 4 cable is enough.