Abstract: A convertible sack is provided which alternatively functions as a sack or tote for carrying objects and as a surface usable for a variety of functions. The sack is formed of a sheet of a flat, subtle material with a hollow circular section, access openings and a cord secured therein. The sack is converted from a flat surface into a sack by pulling the cord through the access openings. The convertible sack has various applications including use as a combination beach tote/blanket, combination diaper bag/changing pad, combination meal tote/seat and combination sack/tent. At least one surface of the sack may be water resistant.