Preheat air fryer to 360º F for 2 or 3 minutes while you prepare the bread cubes.
Slice bread into crouton shaped pieces. Approximately 3-4 cups.
In a bowl, toss the bread cubes with the olive oil, a pinch of salt, and garlic powder. If you are using dry herbs, add them now too.
Put half the bread cubes into the basket of an air fryer (it's okay if they are piled up a bit and touching). Bake at 360ºF until golden.
Shake the basket occasionally, air frying the croutons until they are golden brown on all sides (approximately 5-7 minutes). Cooking time will depend on how large and thick the bread cubes are. Remove from the air fryer and make the second batch.
Once completely cool, store in an airtight container or bag for several weeks.