I have a short (~1ft) USB C cable that "feels" well-built, like a Thunderbolt 3 cable. However, it does not have any branding anywhere so I can't look up the "model" of the cable.

How do I tell its maximum charging capacity, data transfer speed, video transfer capability, etc.? Do I have to test each of them individually to "profile" the cable?

  • I don't think the cable defines the capabilities so much as the charger the cable connects to. – davidgo Aug 12 '20 at 20:03
  • I have a usb c cable that will not fast charge my phone, another one does not do data. There are some crap ones out there and no way to tell other than use it. – Moab Aug 12 '20 at 20:17
  • Actually, not handling data can be a good thing, if using a charging station at an airport or wherever else it might try to pass on malware. – DrMoishe Pippik Aug 12 '20 at 21:18
  • You can't determine this from looking at the cable, though some will have e-marker embedded that can give you some useful information. For cables without an e-marker, the max charge current is often determined by the voltage / IR drop. – Attie Aug 12 '20 at 21:47
  • @davidgo Not sure what you mean. Some cables are rated as 60W max, and some are rated as 100W max. If you connect either to a 100W wall charger, the cable becomes the limiting factor. Of course if you connect a 100W cable to a 60W wall charger, the wall charger will be the limiting factor. – Skeleton Bow Aug 13 '20 at 2:40

The "type" of cable is determined by the plugs (A, B, C). The rest... well, unless the supported specs are not printed on the cable (mainly it's about the USB version, USB 1-4 + Sub Versions) you're out of luck. Then you'll have to revert to tryouts and measuring (and comparing). And as Moab points out correctly there are "special" cables as well optimized for charging etc.

You might also want to take a cable on which you have specs as a reference frame this way you can determine the quality of the cable. Just be aware that factors like quality of the materials, length, past stress, quality of manufacturing etc. do have significant influence.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.