How can I tell whether my USB C cable is a USB 3.1 cable, a passive Thunderbolt 3 cable, or an active Thunderbolt 3 cable?

Question

I have two Thunderbolt 3 devices that each came with their own Thunderbolt 3 cable, plus another USB-C cable that I'm not sure what its capabilities are.

Is there any way I can determine whether the Thunderbolt 3 cables are either passive 20 Gbps cables or active 40 Gbps cables?

And in the case of the unknown USB-C cable, how I can tell whether it's a 10 Gbps USB 3.1 cable, or either of the two types of Thunderbolt 3 cables?

Answer 1

You could ask the manufacturer if it is active or passive. The only thing I read was that active cable have a slightly longer plug. The lightning symbol should tell you if it is a thunderbolt cable (but I think not every manufacturer follow the rules ...).