Getting the mattress size right

When you are looking for particular mattress sizes, don't forget the vertical measurements! Mattress thickness can vary dramatically from as little as six inches to 22 inches. If you decide to use a box spring or foundation, that will increase it still further. If you are buying a mattress for an existing bed frame, don't forget to measure the distance from where the bottom of the place where the mattress will rest up to the bottom of the headboard. Otherwise your headboard will either be a nuisance or invisible.