http://www.techradar.com/news/iphone-x-fast-charges-up-to-50-in-just-30-minutes-but-that-costs-extra

iPhone X, iPhone 8 and iPhone 8 Plus are now official, and you may be pleased to know Apple's latest creations support fast charging. 

This means you can get up to 50% power after 30 minutes on the cable, as 9to5Mac uncovered, if your battery is completely drained from the start.