Full Mattress Toppers

A full mattress topper measures 54 by 75 inches, the same footprint as a full mattress. That makes it 16 inches wider than a twin and exactly the same length, which is the detail most people miss when they upgrade from one to the other.

Yes. Full and double are two names for the same 54 by 75 inch mattress, so a topper sold under either name fits the same bed. Double is the older term, from before queen and king sizes became standard, and some retailers still use it.

No. A full XL is 54 by 80 inches, so the two share the same width and the XL adds five inches at the foot. A standard full topper leaves that last stretch of the bed uncovered, and the two sizes are easy to confuse in a listing, so check the length before ordering.

No. A full mattress is 54 by 75 inches, so a twin topper is 16 inches too narrow and leaves a wide strip of the bed uncovered. The length is the same on both beds at 75 inches, so width alone rules it out, and the full size topper is the one to order.

No. A queen is 60 by 80 inches, so a full topper falls 6 inches short across the bed and 5 inches short down its length. Order the queen size topper instead, which is cut to the larger footprint.

No, it will overhang badly. A twin is 38 by 75 inches, so a full topper is 16 inches too wide even though the length matches exactly. The excess folds down the side of the bed rather than lying flat, so the twin size is the one to order.

Often not. A full is 75 inches long, the same as a twin, so anyone approaching six feet has very little room at the foot of the bed. A topper cannot add length, so if the bed feels short rather than narrow, a twin XL or a queen at 80 inches is the fix.

It is tight. A full is 54 inches wide, which gives each of two sleepers 27 inches, less personal width than one person gets on a twin mattress. A topper matches the 54 inch width exactly and does not change that, so if the bed already feels cramped, a queen gives each person 30 inches instead.

Often not, and it is worth planning for. A 3 or 4 inch topper raises the sleeping surface enough that standard fitted sheets stop reaching the corners, which is the most common complaint after a topper arrives. Add the mattress and topper depths together and look for deep pocket full sheets, remembering that a mattress protector adds around another half inch.