How to measure your child

Weight
Until children can stand still on their own, they should weigh them undressed (without a diaper) on a scale. Once a child can stand still on his or her own, he or she can be weighed on an upright scale and may wear underwear.

Length and height
Infants and babies should be measured lying down. After their second birthday, most children can be measured standing, with their heels close together, legs straight, arms at their sides and shoulders relaxed. Length / height is read to the nearest eighth of an inch (0.1 cm). Once a child begins being measured standing, height becomes the primary measurement instead of length. A child can be up to an inch longer when lying down.

Head circumference
Place a flexible measuring tape just above the child’s eyebrows and ears, and around the back of his or her head where it slopes up prominently from the neck. The goal is to measure the head at the spot where it has the largest circumference. The measurement is read to the nearest eighth of an inch (0.3 cm).