Newborn baby (average)

Newborn baby (average) measures 500.0mm × 350.0mm × 130.0mm. It weighs about 3,400.0g.

Dimensions

Length500.0 mm
Width350.0 mm
Height130.0 mm
Weight3,400.0 g

Source: https://www.cdc.gov/nchs/

Newborn

An average full-term newborn measures about 19.5 inches (49.5 cm) long and weighs approximately 7.5 pounds (3.4 kg) at birth. This page covers typical newborn length and weight ranges, head circumference, and how these measurements are tracked over the first weeks of life.

Dimensions

Measurement Average Typical range
Length 19.5 in (49.5 cm) 18 to 21 in (46 to 53 cm)
Weight 7.5 lb (3.4 kg) 5.5 to 10 lb (2.5 to 4.5 kg)
Head circumference 13.8 in (35 cm) 13 to 14.5 in (33 to 37 cm)

These figures reflect full-term babies born between 37 and 42 weeks of gestation. Length and weight can vary meaningfully within the typical range and still be considered healthy, since factors like genetics and gestational age at birth both play a role.

Growth in the first month

A newborn typically grows about 0.75 to 1 inch (1.9 to 2.5 cm) in length during the first month and gains roughly 1.5 to 2 pounds (0.7 to 0.9 kg), though initial weight loss of up to 10% in the first few days after birth is common and expected before weight gain resumes.

Newborn vs average adult height

Stage Average height/length
Newborn 19.5 in (49.5 cm)
Adult male 69 in (175.3 cm)
Adult female 63.5 in (161.3 cm)

A newborn is roughly a quarter to a third the length of an average adult, and most of that difference in height is gained during infancy and adolescence rather than gradually over an entire lifetime.

Frequently asked questions

How long is an average newborn?

About 19.5 inches (49.5 cm), with a typical healthy range of 18 to 21 inches.

How much does an average newborn weigh?

Approximately 7.5 pounds (3.4 kg), with a typical healthy range of 5.5 to 10 pounds.

What is the average head circumference of a newborn?

About 13.8 inches (35 cm), typically ranging from 13 to 14.5 inches.

Is it normal for newborns to lose weight after birth?

Yes. Losing up to 10% of birth weight in the first few days is common and expected before weight gain resumes.

How much does a newborn grow in the first month?

Typically 0.75 to 1 inch (1.9 to 2.5 cm) in length and 1.5 to 2 pounds (0.7 to 0.9 kg) in weight.

Similar in Size

Frequently Asked Questions

How long is a Newborn baby (average)?

A Newborn baby (average) is 500.0mm (50.0cm) long.

How tall is a Newborn baby (average)?

A Newborn baby (average) is 130.0mm (13.0cm) tall.

How much does a Newborn baby (average) weigh?

A Newborn baby (average) weighs about 3,400.0g.