How much space would all the air sacs in lungs of an adult cover?

If all the air sacs in the lungs of an adult were spread out flat, they would cover an area of about 100 square meters (1,100 square feet). This is roughly the size of a tennis court. The lungs are made up of millions of tiny air sacs called alveoli, which are responsible for exchanging oxygen and carbon dioxide between the air and the bloodstream. The total surface area of the alveoli is enormous, which allows for a large amount of gas exchange to occur.