Question: what is the average head size for a 6 month old?
Answer: Your infant's head will grow about ½ inch every month for the first 6 months. His or her head will grow ¼ inch per month between 6 months and 1 year of age. His or her head should measure close to 17 inches around by the time he or she is 6 months old and 20 inches by 1 year of age.