iOS 15 Compatible Devices
If you own an iPhone or iPod touch that supports iOS 14, then you can upgrade to iOS 15. Apple’s list of iOS 14 compatible devices exactly matches that for iOS 15. Here is a list of iOS 15 supported iPhone and iPod models.
iPhone 12 iPhone 12 miniiPhone 12 ProiPhone 12 Pro MaxiPhone 11 iPhone 11 ProiPhone 11 Pro MaxiPhone XiPhone XRiPhone XSiPhone XS MaxiPhone 8iPhone 8 PlusiPhone 7iPhone 7 PlusiPhone 6siPhone 6s PlusiPhone SE (1st and 2nd generations)iPod touch (7th generation)
The iPhone 13 comes with iOS 15 installed.
iPadOS 15 Compatible Devices
Like with iPhone, if your iPad supports iPadOS 14, then it’s compatible with iPadOS 15. To double-check your iPad model, here is a list of supported devices for iPadOS 15.
iPad Pro 12.9-inch (1st through 5th generations)iPad Pro 11-inch (1st through 3rd generations)iPad Pro 10.5-inch iPad Pro 9.7-inch iPad Air (3rd and 4th generations)iPad Air 2iPad mini (5th generation)iPad mini 4iPad (5th through 8th generations)
Not sure which iPad you have? You can find the iPad model number to see which one you own.