Sinosauropteryx
"Sinosauropteryx" was a small bipedal theropod, noted for its short arms, large first finger (thumbs), and long tail. The taxon includes some of the smallest known adult non-avian theropod specimens, with the holotype specimen measuring only in length, including the tail. However, this individual was relatively young. The longest known specimen reaches up to in length, with an estimated weight of .
Compsognathidae
The other genera in this family are slightly larger than "Compsognathus longipes", but generally similar in size. The largest member of the family Compsognathidae is "Huaxiagnathus", which is estimated from its holotype to be around 5.9 m in length. "Sinocalliopteryx" measures around 2.4 m in length. "Sinosauropteryx" is the most similar to "Compsognathus", measuring at 1.07 m in length at most.