Whether your device charges using a Micro USB, Lightning, or USB-C cable, you may not be charging at optimal speed. It's important to find out what amperage your device was designed to use while charging.

Once you know the intended amperage, make sure that the cable and power supply supports this amperage.


The iPhone 6S+ can charge at a max of 2.4amps, using a 5Watt or higher power supply.

An iPad Air also charges at 2.4amps, but needs a 12Watt power supply.

While the iPhone will fully charge on either power supply, the iPad may display “Not Charging” and fail to fully charge. Furthermore, charging the iPhone on the 12Watt power supply will result in a faster charge. Charging from dead to full could save 1 hour charge time using the 12 watt compared to the 5 watt.

In addition to standard charging, many of the newest devices are capable of "rapid charging." While some companies have a proprietary plug style or name such as "quick charging," or "turbo charging," they all basically mean the same thing. Rapid charging uses a USB-C connector at 5Amps and require a 5V bus in the power supply. The best bet for achieving rapid charging is to use a USB-C power supply and cord.


For many, the search for the optimal charge might need to start with a better understanding of of USB: Welcome to USB 101


The Universal Serial Bus (USB) was invented in the mid 1990s to replace serial, parallel and PS/2 ports. Combining all of these ports into one made devices more compatible and easier to use, thus the term "universal." This was great because rather than needing a separate, unique cord for each brand or peripheral, USB allowed users to easily swap out printers, keyboards, digital cameras, etc. The USB cord could be plugged into any available port on the computer and was capable of transferring information as well as power.  Today, USB is the most common cross-platform technology used for smartphones, PDAs and game consoles.


There are five different versions of USB: 1.0, 1.1, 2.0, 3.0 and 3.1. These version numbers directly relate to the age; 1.0 being the oldest and 3.1 being the newest. They also directly relate to max amperage for charging; 1.0= 0.5A, 2.0=0.5A, 3.0=1.5A, 3.1=3A*.

Quick Tip:  You can generally distinguish USB 3.0 by the blue insert in the connector.



In addition to the version of USB, there are also a number of USB TYPES. USB Type A is the most recognizable with it's rectangular shape. When USB first came out, most people referred to a USB Type A as simply USB. USB Type B came out at the same time as the Type A and was commonly referred to as a USB Printer cable.

USB Type C is the newest type of USB and was released around the same time as version 3.0.  Type C is entirely different in that there is no "right way up" on the USB-C so it can be plugged into its port either way. Additionally, Type C is very small, about a third the size of a traditional Type A. According to How to Geek:

This is a single connector standard that every device should be able to use. You’ll just need a single cable, whether you’re connecting an external hard drive to your laptop or charging your smartphone from a USB charger. That one tiny connector can be small and fit into a mobile device, or be the powerful port you use to connect all the peripherals to your laptop. The cable itself has USB Type-C connectors at both ends — it’s all one connector.

Devices that use USB-C include:

  • Apple MacBook and MacBookPro
  • Huawei Nexus 6P
  • LG Nexus 5X
  • Google Pixel and Pixel XL
  • OnePlus2 & OnePlus3
  • Galaxy Note7
  • Microsoft Lumia 950 & 950XL


*USB 3.1 requires a 5V bus to charge at 3A.

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