The Average Weight & Height of Infants

Not all infants are the same height and weight. Some babies are naturally bigger or smaller than others, and ethnicity, gender and genetics play a role in a child's overall size, according to the KidsHealth website. Doctors use growth charts to track how infants compare to others of the same age, but keep in mind that where a child falls on a growth chart is not necessarily an indicator of good or poor health.

Baby Girl Height

Based on the Centers for Disease Control and Prevention (CDC) growth charts updated in 2000, the average height for a newborn baby girl is about 19 inches. By 1 year, the average height for girls is just more than 28 inches.

Baby Boy Height

At birth, the average baby boy is about 19 1/2 inches long, according to the CDC. For a 1-year-old, height around 29 1/2 inches is average.

Baby Girl Weight

The average newborn baby girl ways about 7 1/2 pounds, according to the CDC; the average 1-year-old girl weights just more than 20 pounds.

Baby Boy Weight

A newborn baby boy weights about 8 pounds on average. By 1 year, the average baby boy weighs about 22 pounds, according to the CDC.

References

• KidsHealth: Growth Charts
• CDC: Length-for-Age Percentiles--Girls, Birth to 36 Months
• CDC: Length-for-Age Percentiles--Boys, Birth to 36 months
• CDC: Weight-for-Age Percentiles--Girls, Birth to 36 Months
• CDC: Weight-for-Age Percentiles--Boys, Birth to 36 Months

Resources

• KidsGrowth: Growth Charts
• Eirpharm: Baby Weight and Height Calculator
• Ask Dr. Sears: Breast-Feeding-Weight Gain (Growth Patterns)
• Ask the Dietitian: Infants and Toddlers under 2 Years
• Your Baby Today: Sizing Up Your Infant