Wash your potatoes, then poke them with a fork all around each one. Pat them dry.
Rub olive oil over each one (generously) and then sprinkle sea salt over the entire outside of each potato.
Place a trivet inside your air fryer if yours uses one (for the Ninja Foodi flip the metal trivet it comes with upside down so it's lower).
Put your potatoes on your trivet so they aren't overlapping.
Close your air fryer lid (on the Ninja Foodi it is the lid that is attached). Set to air crisp, 400 degrees for 35-45 minutes. (timing will depend on size of potatoes, check after 35 min, poke with fork to see if middle is tender)
Take out when time is up, slice and fluff up inside.