Charging Speeds
USB-C cables are mainly rated at 3A and 5A. For USB-C to USB-A cables, we only selected 3A level, because 3A is enough to charge most devices with USB-C ports. The 5A USB-C to USB-A cables have a relatively small application range unless your phones are from Huawei, OnePlus or OPPO. However, these brands have their exclusive fast charging protocols like Huwei’s SuperCharge, Oneplus’s Dash Charge, and OPPO’s VOOC Flash Charge, which are not compatible with some common fast charging protocols. That is to say, USB-C to USB-A cables should not only support 5A but also support their proprietary protocols, which leads to the narrow applicability of 5A USB-C to USB-A cables.
As for USB-C to USB-C cables, 3A is enough to fully power up all existing PD-enabled mobile devices and some low-power-consumption laptops. If you need to juice your high-powered laptop (like a MacBook Pro 15”), then a 5A cable will meet your requirement. And only 5A USB-C to USB-C cables can hit 100W power delivery level.
USB-C to Lightning cables can only charge Apple devices equipped with Lightning ports. Thus, we will be A-OK with them, as long as they support 2.4A.