What's going on with USB-C cable types? Solving the problem where they look the same but are completely different inside!
I'm Makurin, a gadget blogger.
Do you really understand the different types of USB-C cables?
Honestly, USB-C cables all look the same on the outside.
But, they are completely different on the inside!
Some cables can only charge, while others can transfer data at 40Gbps, and some can even output 4K video.
I used to think, "They're all Type-C, so they must be the same," and bought one randomly. It turned out the data transfer for my external SSD was incredibly slow, and when I checked, it was a USB 2.0 cable... lol
In this article, I will organize the differences between USB-C cable types based on three axes: "speed", "charging", and "video", and then explain how to identify them and choose the right one for your needs.
USB-C cables that look the same but are completely different inside
The biggest reason USB-C cables are confusing is that there is only one type of connector shape, but the internal specs vary wildly.
Broadly speaking, they differ in three ways: "transfer speed", "charging performance", and "video output".
Just by understanding these three, you will almost never be confused about choosing a USB-C cable again.
Differences in transfer speed (USB 2.0 to USB4)
The transfer speed of a USB-C cable varies drastically depending on the USB standard it supports.
USB 2.0 has a maximum of 480Mbps.
The cheap cables that appear when you search for "USB-C cable" on Amazon are usually this type.
If you only use it for charging, it's fine, but honestly, it's slow for data transfer.
USB 5Gbps (formerly USB 3.0) has a maximum of 5Gbps, which is about 10 times faster than USB 2.0.
This is sufficient for connecting USB flash drives or external HDDs.
USB 10Gbps (formerly USB 3.1 Gen 2) has a maximum of 10Gbps.
If you want to fully utilize the speed of an external SSD, this is the class you want.
USB 20Gbps (formerly USB 3.2 Gen 2x2) has a maximum of 20Gbps.
It's incredibly fast if you use a compatible SSD, but there are still few compatible devices.
USB4 has a maximum of 40Gbps.
It is compatible with Thunderbolt 3 and also supports video output. It has become mainstream in high-end devices in 2026.
USB4 Version 2.0 has a maximum of 80Gbps (120Gbps asymmetrically).
It is the fastest USB standard as of 2026, but there are still few compatible products.
By the way, the names of USB standards keep changing, and you might see notations like "USB 3.2 Gen 1" or "USB 3.2 Gen 2," but recently the USB-IF has been recommending speed-based naming (USB 5Gbps, USB 10Gbps, etc.) instead.
This is easier to understand, so I will use this notation in this article as well.
Differences in power delivery (charging) performance
USB-C cables also differ in the wattage they can deliver.
They can be broadly divided into three patterns.
Standard cables (up to 60W) are the basic USB-C specification, supporting up to 3A/20V. This is sufficient for charging smartphones and tablets.
Cables with built-in eMarker (up to 100W) have an IC chip (eMarker) inside the cable and support up to 5A/20V. This class is necessary for charging laptops.
EPR-compatible cables (up to 240W) support USB PD 3.1's Extended Power Range. They can even cover charging for gaming laptops. However, compatible cables are still expensive.
The point is that you won't get the maximum wattage unless both the charger and the cable are compatible.
Even if you use a 100W charger, if the cable is only up to 60W, you will only get 60W.
A 60W cable is enough for charging a smartphone, but if you want to charge a laptop, it is safer to choose one that supports 100W.
Whether it can output video
Many people don't know this, but not all USB-C cables support video output.
To output video to an external monitor via USB-C, you need a cable that supports DisplayPort Alt Mode (or Thunderbolt).
With cheap charging cables, the pin wiring required for video output is omitted from the start, so nothing will display even if you connect them.
This is usually the cause of the problem when you think, 'I connected to a monitor with Type-C, but nothing is showing up!'
If you want video output, choose at least a USB4-compatible or Thunderbolt-compatible cable.
How to identify USB-C cables
After reading this far, you're probably thinking, 'I understand they are different inside, but how can I tell them apart?'
Unfortunately, the tricky thing about USB-C is that you cannot tell by looking at them.
However, there are a few ways to distinguish them.
Judging by packaging and logos
The most reliable way is to check the information on the packaging and the logo printed on the cable.
These are the points you should check.
Transfer speed notation: Check if the speed is written, such as 'USB 10Gbps' or 'USB4 40Gbps'
Wattage notation: Often printed on the cable itself, such as '60W', '100W', or '240W'
USB logo: 'SS' logo for USB 5Gbps, 'SS 10' logo for USB 10Gbps, and a logo with the number '40' for USB4
Thunderbolt logo: If there is a lightning bolt mark, it is Thunderbolt compatible. You can also identify the version by the number (3/4/5)
Video output support: Check if it explicitly states 'DP Alt Mode supported' or 'Video output supported'
When buying on Amazon, be sure to check the specifications section of the product page.
If the title only says 'USB-C', there is a high possibility it is USB 2.0.
What is an eMarker?
eMarker is a small IC chip embedded inside a USB-C cable.
This chip holds the cable's specification information (supported speed, supported wattage, etc.) and self-reports to the connected device, saying, 'I am this kind of cable.'
USB 10Gbps or higher cables and 100W or higher cables are required to have an eMarker.
On the other hand, cables without an eMarker are USB 5Gbps or lower and up to 60W.
Cables that say "eMarker included" on the package are proof that they support at least high-speed communication or high-power delivery, so it's a good guideline when choosing.
When in doubt, a Thunderbolt cable is the best
Here is the conclusion for those who think, "I don't know what to buy anymore!"
Thunderbolt cableIf you buy one, you can cover almost everything.
Thunderbolt cables support transfer speed, charging, and video output, so you won't have to worry about whether you can use this cable.
The main options currently are Thunderbolt 4 and Thunderbolt 5.
Thunderbolt 4 supports USB4 (40Gbps), USB PD 100W, and DisplayPort Alt Mode (4K x 2 screens).
Charging, data transfer, and video output are all covered by this one cable. The price is around 2,000 to 3,000 yen.
Thunderbolt 5 is the higher-end version.
80Gbps bidirectional, and in addition to the overwhelming speed of up to 120Gbps with Bandwidth Boost, it also supports USB PD 240W.
It also has 8K/60Hz video output and compatibility with USB4 V2.0 (80Gbps), so it's on a different level in terms of specs.
Since the beginning of 2026, Thunderbolt 5-compatible docks and cables have been announced all at once, and products are starting to appear one after another from manufacturers such as OWC, CalDigit, and Anker.
However, Thunderbolt 5 cables still cost around 3,000 to 5,000 yen, and compatible devices (on the PC side) are limited to high-end models.
The best value for money at the moment is Thunderbolt 4.
But for those who have bought a new MacBook or high-end notebook, or those who handle video editing or large-capacity data, it is worth choosing Thunderbolt 5.
Whichever you buy, there is backward compatibility, so you don't have to worry about "buying it but not being able to use it."
By use case! How to choose a USB-C cable
Finally, here is a summary of "just buy this" for each use case.
If you're just charging your smartphone, this is all you need
If your goal is just to charge your smartphone, honestly, you don't need to be that picky.
USB-C to USB-C cable
USB PD compatible (if you want fast charging)
60W support is enough (smartphones charge at 20-30W)
1 to 1.5m length is easy to use
Charging speed is unrelated to the transfer standard, so a USB 2.0 cable is perfectly fine.
All you need to check is whether it is "PD compatible" or not.
You can't go wrong if you choose a manufacturer like Anker or CIO.
These are the specs you need if you want to transfer data
If you want to exchange data using an external SSD or USB flash drive, I recommend a USB 10Gbps compatible cable.
With USB 5Gbps, you can't fully utilize the speed of an external SSD, and cables and devices supporting USB 20Gbps or higher are expensive.
In terms of the balance between cost-performance and practicality, 10Gbps is the sweet spot.
Choose a cable that says "USB 10Gbps" or "USB 3.2 Gen 2" on the package.
For video output or docking station connections, this is the only choice
If you want to output video from your laptop to a monitor or use a docking station, the Thunderbolt cable I mentioned earlier is the best.
Thunderbolt 4 supports 4K/60Hz x 2 screens, and Thunderbolt 5 supports up to 8K/60Hz.
Since this one cable can handle video output, data transfer, and charging, you won't need to switch between different cables for different purposes.
Thunderbolt 4 is enough if you're just outputting to one 4K monitor. If you're considering an 8K monitor or a setup with three or more screens, choosing Thunderbolt 5 will keep you future-proof.
Summary: Choose USB-C cables by what's inside, not by how they look
USB-C cables all look the same, so it's easy to just pick one at random, but they are completely different things when it comes to "transfer speed," "charging wattage," and "video output support."
Just by getting into the habit of checking the logos and specifications on the packaging, you can significantly reduce the risk of buying the wrong cable.
If you're confused, just keep one Thunderbolt cable on hand, and it will cover charging, data transfer, and video output.
For cost-performance, go with Thunderbolt 4; for specs, go with Thunderbolt 5. This is the clearest, most straightforward answer.
Once you understand the differences between USB-C types, the stress of choosing a cable will disappear.
Thanks for reading, this was Makurin!
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