Which iPhone Models Are Compatible With iOS 12?
In short, if your iOS device supports iOS 11 then it will also support iOS 12. That means every iPhone released from the iPhone 5S on will be compatible. This includes the iPhone SE, iPhone 6, iPhone 7, etc.
Most recent iPad models are also supported including the iPad mini 2, iPad mini 3, iPad mini 4, the iPad Air & iPad Air 2, iPad (5th generation and newer), and all iPad Pro models.