Twin mattresses measure 38" x 75", making them the smallest standard adult mattress size. Designed for single sleepers, twin-size mattresses fit comfortably in rooms as small as 7' x 10' and are the most budget-friendly mattress option. Perfect for children's bedrooms, bunk beds, daybeds, trundle beds, and compact guest rooms, Twin mattresses work well for children through early teens and adults under 6 feet tall. Browse our entire Twin selection below.