Starting with iOS 11.2, iPhone 8, 8 Plus and iPhone X to support 7.5W fast charging support at 7.5 watts using compatible Qi-based wireless charging accessories. With the current iOS 11.1.1, all the three device charge at a speed of 5W using Qi wireless chargers.
Apple has promised that faster speeds would be available in the future updates and just as it promised it appears to be live on iOS 11.2. MacRumors has received a top from RAVpower post which they have confirmed that the phones were indeed charging at faster speeds.
Belkin charger that Apple sells which supports 7.5W was able to charge the iPhone X from 46 to 66% in just thirty minutes, while the same phone was able to charge from 46 to 60% with the accessory that doesn’t support 7.5W charging speeds.
Obviously, the 7.5W charges quicker than the regular 5W and with 7.5W you will be able to charge you’re iPhone 8, 8 Plus and X quicker than usual. iOS 11.2 is currently in beta and is limited to developers and public beta testers, the public release is expected in the coming weeks or a month. The 7.5W fast charging only supports Apple’s wireless charging supported iPhones with iOS 11.2 installed."iOS 11.2 to bring support for 7.5W wireless charging on iPhone 8, 8 Plus and iPhone X",