Tawa was estimated to have been 2 m (6.5 ft) long, almost 2.5 feet at the hips. Other estimates suggest that Tawa weighed 40 kilograms (88 pounds) at most.[4] The holotype, a juvenile individual, cataloged GR 241, consists of a mostly complete but disarticulated skull, forelimbs, the pectoral girdle, a partial vertebral column, hindlimbs, the pelvic girdle, ribs, and gastralia. The determination was made that this specimen is a juvenile based on the presence of an open braincase and unfused neurocentral sutures.[3] An isolated femur GR 244 suggests that adults were at least 30% larger than the juvenile holotype. Tawa preserves characters that can be associated with different dinosaur taxa. It's skull morphology resembles that of coelophysoids and the illium approximates that of a herrerasa