New Baby weight should after birth

Chart of average weights

The following weights for maleTrusted Source and femaleTrusted Source babies are from the World Health Organization (WHO). Both the Centers for Disease Control and Prevention (CDC) and American Academy of Pediatrics recommend using WHO’s charts for children up to 2 years old.

Here’s a breakdownTrusted Source for the first year:

Age	50th percentile weight for male babies	50th percentile weight for female babies
Birth	7.8 lbs. (3.5 kg)	7.5 lbs. (3.4 kg)
0.5 months	8.8 lbs. (4.0 kg)	8.4 lbs. (3.8 kg)
1.5 months	10.8 lbs. (4.9 kg)	9.9 lbs. (4.5 kg)
2.5 months	12.6 lbs. (5.7 kg)	11.5 lbs. (5.2 kg)
3.5 months	14.1 lbs. (6.4 kg)	13 lbs. (5.9 kg)
4.5 months	15.4 lbs. (7.0 kg)	14.1 lbs. (6.4 kg)
5.5 months	16.8 lbs. (7.6 kg)	15.4 lbs. (7.0 kg)
6.5 months	18 lbs. (8.2 kg)	16.5 lbs. (7.5 kg)
7.5 months	19 lbs. (8.6 kg)	17.4 lbs. (7.9 kg)
8.5 months	20.1 lbs. (9.1 kg)	18.3 lbs. (8.3 kg)
9.5 months	20.9 lbs. (9.5 kg)	19.2 lbs. (8.7 kg)
10.5 months	21.6 lbs. (9.8 kg)	19.8 lbs. (9.0 kg)
11.5 months	22.5 lbs. (10.2 kg)	20.7 lbs. (9.4 kg)
12.5 months	23.1 lbs. (10.5 kg)	21.4 lbs. (9.7 kg)