2023 ยท You can fast charge your iPhone 8 or later up to 50 percent battery in around 30 minutes. Find testing information for various iPhone models. To fast charge, you need an iPhone 15 model with a USB-C cable like the one that came in the box or an earlier iPhone model with a USB-C to Lightning cable and one of these adapters: Apple 18W,* 20W, 29W.