Many people make the mistake of thinking a full size mattress, measuring 54" wide and 75" long, sleeps two comfortably. However, a full mattress is more ideally suited for sleeping a single person, since when you divide the full mattress size in two, it's only as wide as a typical crib. Check out affordable full bed mattress options, including many on sale right now. Full beds are the most common hotel room beds even when queens are advertised.