The head circumference of infants will have different values at different ages, and the standards for head circumference differ for male and female infants. The standard head circumference for newborn babies ranges from 31.8 to 36.3 centimeters for male babies and from 30.9 to 36.1 centimeters for female babies; After 30 days of life, the standard head circumference of male babies ranges from 35.4 to 40.2 centimeters, and that of female babies ranges from 34.7 to 39.5 centimeters; The standard head circumference of male infants at 60 days of age ranges from 37.0 to 42.2 centimeters, and that of female infants ranges from 34.7 to 39.5 centimeters. Head circumference measurements are most valuable up to 2 years of age. Head circumference is a measurement of the length of the head from the upper edge of the arch of the eyebrow to the occipital node, which is symmetrical around the head, and is very closely related to the development of the brain and skull. When the head circumference is too big or too small, it is necessary to go to the hospital in time.