Rinse kale leaves under cool running water to remove any debris. Dry in a salad spinner or pat dry with a clean towel.
Using a knife or your hands, remove the kale stem. Tear or cut the kale leaves into roughly 2-inch pieces.
In a medium bowl, toss the kale with olive oil, salt, garlic powder, and onion powder. Alternatively, spray the kale leaves with oil.
Preheat the air fryer to 275F. Place kale in the air fryer basket, careful not to overlap pieces too much. You will likely need to air fry the kale in batches.
Air fry at 275F for 5 minutes, until the kale is very crispy but not browned. If the kale isn't crispy enough, cook an extra 1 minute at a time.
Keep a close eye on the kale chips as they cook. They are best enjoyed immediately but can be stored at room temp for 3-4 days. Recrisp in the air fryer.
Notes
Air frying kale at a low temp dehydrates the kale and cuts down on the risk of burning the kale, but you should still keep a close eye on the air fryer while the kale is cooking.