A baby's and child's growth: Rule of thumb

A baby's and child's growth: Rule of thumb

Benchmarks for length, weight, and head size

keeping track of a child's growth

Benchmarks of your baby's and child's growth.

  • Length
    • The average length of a newborn is 20 inches. Most babies grow 1-2 inches in the first month, about 10 inches the first year (increasing their birth length by 50%) 4-5 inches the second year and two more inches each year between 2 and 12
    • To predict adult height, double child's height measured at age 2. Girls usually stop growing between ages 14 and 16 , while boys grow until age 16 or even 20. 
  • Weight 
    • The average weight of a newborn is 7 pounds. The average newborn gains ⅔ ounce each day; 4-6 ounces each week the first month; 6-8 ounces each week the next 2 months, then 1 pound a month until 6 months and less there after
    • Babies normally double their birth-weight by 6 months, triple it by 1 year, and quadruple their birth-weight by age 2. 
  • Head Size 
    • A baby's head is ⅓ of body length at birth. A baby's brain grows faster than any other part of the body and normally doubles in size by 12 months (which makes it ¾ adult size). An adults head is about ⅛ of body height. 
    • Babies' brains are twice as active as adults', using up half of the calories eaten.Babies are born with 100 billion brain cells and only 50 million connections. By the end of the first year there are 1,000 trillion connections.

Adapted from Nurturing with Nutrition by Dr. Melanie Bezarte and Lucille Beseler, RDN