The easiest way to check if your salmon is cooked is to press down on it gently with a fork. If the flesh flakes easily, then it's done. You can also check for doneness with an instant read thermometer inserted into the thickest part of the fish. The FDA recommends cooking salmon to an internal temperature of 145°F, which is well done. If that's how you like your salmon, remove it from the air fryer when it reaches 140°F since it will continue to cook after it's taken out. If you like your salmon a little less cooked (like I do), remove it when it reaches 130-135°F.