Yes, the 30w charger can charge the iPhone, but it should be noted that the maximum charging current of the iPhone is only 2.4A, and the charger that exceeds this current does not help the iPhone, but will increase the heat of the phone and damage the battery. Therefore, when using a 30w charger to charge an iPhone, you need to make sure that the charger supports Apple's fast charge protocol, and do not use more than 2.4A output current.