Preheat the air fryer to 400°F / 200°C for 3 minutes.
Mix baking powder, garlic powder, smoked paprika, onion powder, black pepper, and salt in a small bowl.
Rub the drumsticks with olive oil, then coat evenly with the seasoning mixture.
Arrange drumsticks in a single layer in the air fryer basket without touching.
Air fry at 400°F / 200°C for 20 minutes, flipping halfway, until the skin is golden and crisp and the internal temperature reaches 165°F / 74°C.
Rest for 3 minutes before serving so the juices redistribute and the skin stays crackling crisp.