Twin Smaller or narrower rooms (say anything under 9 ½ by 7 ½ feet, the smallest ADA-approved size room to fit a full mattress) do well with twin beds. These mattresses still fit in larger ...

body size, if you share a bed, and how much you like to sprawl. Based on five years of professional mattress testing, I've outlined the six standard sizes in our mattress size chart below and ...