Ann is a small 13-year-old girl, with blonde hair wrapped in a ponytail. She wears glasses, an orange jacket, maroon jeans, dark gray boots, and a red shirt that says: "UFO's: They're already here".
Ann is a highly intelligent girl, but most Gravity Falls residents don't see it, and tease her a lot. She is a great planner, even though half of these plans end up going down the drain. She is rather antisocial, having almost no friends. She is also highly emotionally sensitive, tending to lash out at anything if it's severely angering her. She is also very secretive, usually trying to hide her quote-on-quote "paranormal antics" from her father, who thinks she's crazy for believing in that sort of thing, but loves her anyway.