Hello. The rack is 6' long and just over 3' tall. It was designed to fit against the six foot wide brick wall pictured in the photos. The height was determined by what was available in the scrap yard at the time. No reason why you can't build longer or higher....or smaller. I built a smaller version last season, but decided a bigger one was in order. So, I built the one pictured over this weekend.
There are about 2 cords of firewood in the back yard, stacked between trees. My goal was to have a supply nearer the house to draw on during our cold snaps...then refill the rack between the cold snaps and so on throughout the winter.
I believe you could build just about any size of rack you want, or build multiple racks of a convenient size.