4 aircraft and 5 cabin layouts, from the A320 to the A321neo. Pick one for its seat map, the best seats and the seats to avoid.
There are seat maps for 4 Spirit Airlines aircraft here: the Airbus A320, the Airbus A320neo, the Airbus A321 and the Airbus A321neo.
The Airbus A321neo, with 235 seats: 235 Economy in its main layout.
The Airbus A320, with 28" to 37" of seat pitch in Economy and seats 18" to 22" wide.