If you find your feet dangling over the edge of a twin, you’ll need an 80-inch mattress. Twin XL beds are the narrowest 80-inch bed. If you have a small space but need extra length, this may be the size for you.
Tall active sleepers may want to consider a queen bed if they have the space. The queen’s extra width will accommodate more tossing and turning. The tallest sleepers may need to go even longer, either with the 60 by 84-inch California queen or the 72 by 84-inch California king.