Is there any way I can test the capabilities of a USB-C cable, perhaps with an external device?

I have a USB-C cable that has absolutely no markings on it. I don't know where it came from, so I don't know what kind of cable it is. I think it's a Thunderbolt 3 cable, but I'm not sure. It doesn't have the characteristic lightning bolt icon on it.

Given that I have several Thunderbolt 3 devices, is there any way I could test the capabilities of this cable using those devices? I have two Thunderbolt 3 hubs (one of which is a CalDigit TS3 Plus) and an external display, which when connected presents as three USB devices on a USB 2 hub, and a 1080p DisplayPort monitor.

Perhaps I could try to transmit as much data along the cable as possible and see where it tops off, but I'm not sure how to do that. Of course I'm open to other, possibly better ideas too.

How can I test a USB C cable?

Two possibilities spring to mind. Caveat, I haven't tried any of them ...

1. Software:

   USBCheck is an Android app that performs basic testing:

   USBCheck is an app that’s designed to help determine whether your USB Type-C cable is up to spec. The app checks the current draw of a cable while it’s plugged into your phone. If it notices that the cable is receiving the correct amount of power then it’ll spit back a positive result. If not? It spits a negative one.

   CheckR another Android app

   It is designed for testing Type A to Type C cables/connectors. In other words, anything that you would use to charge with all of your old/existing USB charging stuff that as the Type A port (the USB port matching the one on your computer). Type C to Type C like the one that came with your Nexus 5X/6P will register as a false negative—those are safe to use.

   There are other apps listed here How to Test If Your Android Charging Cable Is Working Properly

2. Hardware:

   Around UKP 25.

   USB C Power Meter Tester, Eversame USB Voltmeter Ammeter Load Tester with Braided USB C to USB C Cable(1.5Ft/50cm) - Test Speed of Charger Cables - PD 2.0/3.0 QC 2.0/3.0/4.0: Amazon.co.uk: Business, Industry & Science

   It can be used to measure input Voltage, current, power, capacity, energy. Support quick charger recognition; USB charger current testing; data wire resistance value testing; QC2.0/QC3.0, Voltage/Current/Power Detection; data store; cable impedance measurement, power bank capacity and energy testing. Featured with Quick Charge Recognition Interface, it can recognize QC multiple protocols such as PD QC2.0 QC3.0/4.0 MTK.

Given the test results it may be possible to work out what kind of cable it is ...

Further Reading:

• How do I work out if a USB-C cable is safe to use? - Super User