The iphone11's fast charge is 18 watts, which supports the 9V\/2A input specification, and if you use a charger that exceeds this specification, it usually peaks at 18 watts. However, when charging the iphone11, it is generally only the first 80% is fast charge, and then it will slowly decline and become slower, and it takes about 1 hour to use fast charge from 0% to 100%
The iPhone 11 supports 18 watts of fast charge. Fast charge is a charging method that can bring the battery to or near a fully charged state within 1 to 5 hours. It is often used for charging traction batteries when they need to be restored to a fully charged state in a relatively short time.