iPhone 15 charging slowly? How to fast charge iPhone with USB-C

The charging situation for the iPhone 15 and iPhone 15 Pro this year has changed. Apple’s proprietary Lightning port has been replaced with USB-C, so now you can charge your phone with almost any USB-C cable and USB-C power adapter that you can find online. But what exactly do you need to make sure you can charge your iPhone battery as fast as possible?

As USB-C is an open standard, you can use pretty much any USB-C cable you can find. The iPhone 15 comes with a nice woven braided cable in the box, but you can use any USB-C cable you can find — including those marketed as ‘Android’ phone cables. However, if it seems like your iPhone is charging slowly, you probably need to change your charging brick.

Back when Apple included accessories in the box, the iPhone came with small 5-watt power adapters. As they were included with the iPhone for such a long time, there are lot of these still out in the world. If you have one of these, it is perfectly safe to use with iPhone 15; you just need a USB-C to USB-A cable to plug in.

However, it will only charge your phone at 5W speed. This was fine when the battery capacities of smartphones was much smaller five years ago, but the iPhone batteries are much bigger these days. As a result, charging at 5 watts can take four or five hours to go from zero to 100%. It is slow.

Fast charge iPhone 15

To fast charge iPhone 15, you’ll need a higher wattage charging brick. The iPhone USB-C port can technically receive power up to 27 watt speeds, but practically speaking there are diminishing returns on charging speed above ~20-watts. So, with a USB-C cable and an Apple 20 W USB-C power adapter, you can charge the iPhone 15 from zero to 50% in about 30 minutes, and from zero to 100% in under 2 hours.

However, you aren’t limited to using Apple accessories. Plenty of higher-wattage USB-C charging options are on the market that are more convenient than Apple’s adapters, like this dual USB-C compact charger from Anker. It is also perfectly safe to use power adapters that are rated higher than 20 watts; they will automatically charge your iPhone at the maximum speed that it supports.

For example, this means if you have a USB-C MacBook power adapter, you can use that and charge your phone at full speed too. If your MacBook itself is plugged into power and charging, you can even connect your phone into one of the laptop’s USB-C ports and charge at near-full speed.

In fact, USB-C means that you can now fast charge all of your Apple devices with the same cable and 60-watt (or higher) MacBook power adapter.