Question: is 20 inches big for a baby?
Answer: Understanding baby size It's the same as their height, but height is measured standing up, whereas length is measured while your baby is lying down. The average length at birth for a full-term baby is 19 to 20 inches (about 50 cm). But the range for most newborns is between 18 and 22 inches (45.7 to 60 cm).