As far as I know all iPhones from the 6 to date, handle fast charging. If you have an iPad, you can use that charger which is quicker than the charger that ships with the iPhone, and if you own a Macbook Pro that ships with the USB-C charger, use that. When I travel I only carry one charger (the Macbook Pro's charger) for all three (iPhone 6Plus, iPad Air 2 and MacBook Pro). You should be good out of the box, with the iPhone X.