Wash and quarter the potatoes. Rinse them to remove excess starch. Pat dry with a paper towel.
Put the cubed potatoes in the air fryer basket. Spray lightly with cooking oil. Shake the basket and spray again. Season with salt.
Cook the potatoes at 400 degrees F for 17-25 minutes, shaking the basket halfway through. They're done when they're crispy and cooked through to your liking.
Notes
Keep in mind that not all potatoes will cook at the same speed, so you may need to adjust the cooking time to get your desired results. I always start with 17 minutes and go from there.
All air fryers have different wattage and may cook at different rates. You may need to adjust the time or temp for the best results.