Preheat the air fryer to 400°F / 200°C for 3 minutes.
Toss the sweet potato cubes with olive oil, smoked paprika, garlic powder, black pepper, and salt until evenly coated.
Arrange the sweet potatoes in a single layer in the air fryer basket without overcrowding.
Air fry for 15 minutes at 400°F / 200°C, shaking the basket halfway through, until the edges are crisp and golden.
Check at 13 minutes — the sweet potatoes should be fork-tender inside with crispy edges; add 2 more minutes if needed.
Serve immediately while hot for the best texture and flavor.